Chef Juliette
The Preparation of Soups
Préparation des Potages teaches the first obligation of soup: it must announce the dinner in one clear, savory spoonful, then reach every guest fiercely hot in a properly warmed bowl.
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Complete Gratin
Created by Chef Juliette
Raw potatoes, duxelle sauce, and buttered chapelure meet the oven together, then finish as one: tender slices below, a properly reduced border, and a bronzed crust that stays crisp.
Side Dishes
French
Comfort Food
Dinner Party
Special Occasion
30 min
Active Time
1 hr cook•1 hr 40 min total
Yield4 servings
Gratin complet de pommes de terre (complete potato gratin) teaches timing by proportion. The one true thing to know before touching a pan is this: the potatoes, the sauce, and the crust must finish together. Too much sauce leaves cooked potatoes swimming beneath a finished crust; too little disappears while the potatoes are still firm. Match the quantity of sauce to the thickness of the food and the heat of the oven. That is the dish.
The original method assumed a saucier balancing reductions, a stockpot that never cooled, and a salamander ready to correct the surface at the final moment. At home, a shallow gratin dish, evenly sliced potatoes, measured sauce, and the upper third of the oven do the same work. A brief pass beneath the broiler replaces the salamander only if the crust needs it. The separate pan reduction used to repair careless scaling is brigade scaffolding and goes; the simultaneous finish stays. One cook, one stove, one evening.
When it is right, a knife slips through the potatoes without resistance, the duxelle-rich sauce bubbles thickly at the rim, and the chapelure forms a crimped, butter-gold crust rather than a loose scattering of crumbs. The one step that decides it is calibration: slice every potato 3 mm thick and begin with sauce that coats a spoon while still pouring freely.
The gratin complet belongs to the codified Parisian classical kitchen, where gratins were distinguished by whether their principal ingredient entered the dish raw or already cooked. In a complete gratin, the raw food cooks while the sauce reduces and the surface forms its crust; cheese is not the definition, because gratin names the browned coating itself. The method traveled naturally from the grand kitchen to bourgeois home tables, where one oven and a well-judged baking dish replaced the separate hands of the brigade.
The technique, the tradition, and the story behind every dish.
Discover Culinary ExplorerIngredients
Yukon Gold or Charlotte potatoes
Quantity
2 pounds (900 g)
peeled and sliced 1/8 inch (3 mm) thick
button or cremini mushrooms
Quantity
2 cups (480 ml / 180 g)
thinly sliced
shallots
Quantity
1/4 cup (60 ml / 40 g)
finely chopped
Ordinary or Dry Duxelle
Quantity
1 cup (240 ml / 200 g) Ordinary or Dry Duxelle (No. 223)
prepared and ready to use
unsalted chicken stock
Quantity
3/4 cup (180 ml / 180 g)
divided
heavy cream
Quantity
3/4 cup (180 ml / 180 g)
unsalted butter
Quantity
6 tablespoons (90 ml / 85 g)
divided
chapelure (fine fresh breadcrumbs)
Quantity
3/4 cup (180 ml / 45 g)
fine sea salt
Quantity
1 1/2 teaspoons (7.5 ml / 9 g)
freshly ground black pepper
Quantity
1/2 teaspoon (2.5 ml / 1 g)
fresh lemon juice
Quantity
2 teaspoons (10 ml / 10 g)
flat-leaf parsley
Quantity
2 tablespoons (30 ml / 8 g)
finely chopped
| Ingredient | Quantity |
|---|---|
| Yukon Gold or Charlotte potatoespeeled and sliced 1/8 inch (3 mm) thick | 2 pounds (900 g) |
| button or cremini mushroomsthinly sliced | 2 cups (480 ml / 180 g) |
| shallotsfinely chopped | 1/4 cup (60 ml / 40 g) |
| Ordinary or Dry Duxelleprepared and ready to use | 1 cup (240 ml / 200 g) Ordinary or Dry Duxelle (No. 223) |
| unsalted chicken stockdivided | 3/4 cup (180 ml / 180 g) |
| heavy cream | 3/4 cup (180 ml / 180 g) |
| unsalted butterdivided | 6 tablespoons (90 ml / 85 g) |
| chapelure (fine fresh breadcrumbs) | 3/4 cup (180 ml / 45 g) |
| fine sea salt | 1 1/2 teaspoons (7.5 ml / 9 g) |
| freshly ground black pepper | 1/2 teaspoon (2.5 ml / 1 g) |
| fresh lemon juice | 2 teaspoons (10 ml / 10 g) |
| flat-leaf parsleyfinely chopped | 2 tablespoons (30 ml / 8 g) |
Equipment Needed
- •Shallow 2-quart (2-liter) oval gratin dish
- •Mandoline or sharp chef's knife
- •Small saucepan
- •Thin paring knife for testing the potatoes
Instructions
- 1
Calibrate the sauce
Heat the oven to 375°F (190°C) with a rack in the upper third. Stir the Ordinary or Dry Duxelle (No. 223) with 1/2 cup (120 ml) of the stock and all the cream in a small saucepan. Bring it just to a simmer, stirring, then judge the consistency: it should coat the spoon and fall from it in a broad ribbon while remaining loose enough to run between the potato slices. If it stands like paste, add the reserved stock a tablespoon at a time; if it runs like broth, simmer it for two or three minutes. Keep any remaining stock hot for the rescue later.
- 2
Arrange the gratin
Butter a shallow 2-quart (2-liter) gratin dish with 1 tablespoon (15 ml / 14 g) of the butter. Arrange half the potatoes in close overlapping rows, season with half the salt and pepper, then tuck half the raw mushroom slices and shallots between the rows and around the perimeter. Repeat with the remaining potatoes, seasoning, mushrooms, and shallots. Do not rinse the sliced potatoes; their surface starch helps bind the reducing sauce.
- 3
Cover and crust
Pour the warm duxelle sauce evenly over the potatoes, nudging the dish so it settles into every gap. The sauce should rise close to, but not cover, the uppermost slices. Sprinkle the chapelure over the entire surface without pressing it down. Melt the remaining 5 tablespoons (75 ml / 71 g) butter and spoon it generously across the crumbs, leaving no dry islands. We don't apologize for butter. Bake immediately, before the raw mushrooms begin releasing their moisture.
- 4
Finish all together
Bake uncovered for 50 to 60 minutes. Begin checking at 45 minutes: a thin knife should slide through the center without a firm or crunchy spot, the sauce should bubble slowly and glossily around the rim, and the chapelure should be deeply bronzed. If the crust darkens while the potatoes remain firm, cover only the browned surface loosely with parchment, lower the oven to 350°F (175°C), and continue cooking. If the sauce disappears before the potatoes soften, pour a few tablespoons of the reserved hot stock down the inside edge of the dish, never over the crust. If the potatoes are tender but the sauce remains loose, shield the crust and bake for another 5 to 10 minutes. Ça se rattrape.
- 5
Set the gratin
Remove any parchment. If the surface needs its final color, place the dish beneath a hot broiler for 30 to 60 seconds, watching without looking away; this replaces the salamander and is only a finish, not a second cooking. Take the gratin from the oven, squeeze the lemon juice over the crust, and scatter with the chopped parsley. Rest for 10 minutes so the sauce settles around the potatoes without softening the top, then carry the baking dish straight to the table. À table!
Chef Tips
- •Use a shallow 2-quart (2-liter) dish. A deep casserole changes the timing completely: the surface bronzes while the buried potatoes remain firm, and no amount of hopeful waiting corrects the geometry.
- •Yukon Gold and Charlotte potatoes hold their overlapping shape while giving the sauce enough starch to bind. Slice them evenly with a mandoline or a patient knife. Thick and thin slices in the same dish cannot finish together.
- •Chapelure means fine fresh breadcrumbs here. Coarse dry crumbs sit like gravel and scorch in patches; fine crumbs drink the melted butter and join the sauce to form the proper crimped crust.
- •There is no cheese in this formula. The crust comes from sauce, chapelure, butter, and direct heat, exactly as the method requires.
- •Serve beside roast chicken, veal, or a simple joint of beef. A dry white wine with enough body for mushrooms, or a light red without heavy tannin, suits it neatly.
Advance Preparation
- •Have the Ordinary or Dry Duxelle ready before beginning. It can be prepared up to three days ahead and kept covered in the refrigerator.
- •The mushrooms and shallots may be cut up to four hours ahead and refrigerated separately. Slice the potatoes only when the sauce and oven are ready, because soaking removes the starch the gratin needs.
- •Assemble the gratin immediately before baking. A filled dish left standing grows watery as the raw mushrooms and salted potatoes release moisture.
- •Leftovers keep for two days under refrigeration. Reheat uncovered at 375°F (190°C) until the edge bubbles and the crust regains its color.
Frequently Asked Questions
Nutrition Information
1 serving (about 390g)
Calories
610 calories
Total Fat
40 g
Saturated Fat
25 g
Trans Fat
1 g
Unsaturated Fat
13 g
Cholesterol
110 mg
Sodium
1100 mg
Total Carbohydrates
55 g
Dietary Fiber
7 g
Sugars
8 g
Protein
13 g
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