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Food Lab · Experiment 028
Roasted Garlic French Onion Mushroom Gnocchi
Golden potato gnocchi nestle in mushroom-onion gravy under bubbling Gruyère and thyme.

The formula
Ingredients
Roasted garlic and onions
- 1 whole garlic head
- 1 tsp olive oil
- 2 tbsp unsalted butter, divided
- 2 large yellow onions, thinly sliced
- ½ tsp fine salt, divided
- ¼ cup water
Gnocchi skillet
- 1 lb shelf-stable potato gnocchi
- 6 cups water, for boiling gnocchi
- 8 oz cremini mushrooms, sliced
- 1 tbsp olive oil
- 1 tbsp all-purpose flour
- 1 cup unsalted vegetable broth
- 1 tsp Dijon mustard
- 1 tsp fresh thyme leaves
- ¼ tsp black pepper
- ¾ cup (85 g) grated Gruyère
Equipment
Oven-safe skillet, baking dish, foil, saucepan, colander
Allergens and ingredient notes: Wheat, milk; gnocchi may contain egg. Use vegetarian-labeled Gruyère if needed.
The process
Step by step
- Heat the oven to 400°F (200°C). Slice the top off the garlic head to expose the cloves, place on foil, drizzle with its 1 tsp olive oil, and wrap. Roast in a small dish for 35–45 minutes until soft. Cool enough to handle, then squeeze the cloves into a bowl and mash.
- Meanwhile, melt 1 tbsp butter in the oven-safe skillet over medium-low heat. Add onions and ¼ tsp salt. Cook 25–30 minutes until deep golden, adding the measured ¼ cup water a little at a time if needed to loosen browned bits. Transfer onions to a bowl.
- Bring the gnocchi water to a boil in a saucepan. Cook gnocchi according to its package, usually 2–3 minutes until floating, then drain well. Heat the separate 1 tbsp olive oil in the skillet over medium-high heat and brown gnocchi for 4–5 minutes, turning gently. Transfer to the onion bowl.
- Add the remaining 1 tbsp butter and mushrooms to the skillet. Cook 6–8 minutes until browned. Sprinkle in flour and stir 1 minute. Slowly stir in broth, then add mashed roasted garlic, Dijon, thyme, pepper, and the remaining ¼ tsp salt. Simmer 2–3 minutes until lightly thickened.
- Fold onions and gnocchi into the sauce. Sprinkle all Gruyère over the skillet and bake for 8–10 minutes, until bubbling and golden at the edges. Use an oven mitt for the hot handle. Divide among four bowls.
The Devotti twist: A whole roasted garlic head thickens and sweetens the onion gravy without heavy cream.
Make ahead and storage
Refrigerate within 2 hours; use within 3 days. Reheat covered until 165°F (74°C).
Image: AI-generated recipe illustration; homemade results and presentation will vary.
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