Step 1

Make the tomato sauce: Put the olive oil and garlic in a large heavy-bottomed saucepan. Set over medium heat. Cook, pressing on the garlic a couple of times, until it begins to sizzle and release its fragrance. Don’t let it brown. Stir in the chili pepper, then add the passata (or tomato purée) and a pinch of salt. Bring the sauce to a boil, then lower the heat to medium-low. Let the sauce simmer gently until thickened and flavorful, 20 to 30 minutes.

Step 2

Finish the sauce: Taste and add more salt if necessary. Tear up a handful of basil leaves and stir them into the sauce. Turn off the heat and remove the garlic. Cover to keep the sauce warm.

Step 3

Get ready: Set an oven rack in the top third of the oven and preheat the oven to 400°F. Bring a large pot of water to a rolling boil and season with salt. Coat a large oven-proof baking dish in a thin layer of olive oil. Spoon a ladleful of sauce into the dish and set near your stove.

Step 4

Cook the gnocchi: Gently drop the gnocchi into the boiling water, in batches if necessary. They should float to the surface within 30 to 45 seconds. Using a large skimmer or slotted spoon, transfer half the gnocchi to the prepared baking dish. Spoon a layer of sauce on top.

Step 5

Layer: When half the gnocchi are in the baking dish, spoon more sauce on top and sprinkle with half of the mozzarella. Finish cooking the gnocchi, adding them to the baking dish as you go. Spoon more sauce on top and scatter on the remaining mozzarella. Finish with a layer of sauce and sprinkle with a handful of Parmigiano cheese.

Step 6

Bake: Bake for 5 to 8 minutes, just until bubbly. To brown the top, turn on the broiler and slide the baking dish under the broiler for 1-2 minutes. Serve hot.