Heat 3 tbsp olive oil in a 10-inch skillet over medium heat. Add the sliced garlic and cook for 2 to 3 minutes until pale gold, stirring often. Do not let it brown.

Add the crushed San Marzano tomatoes, 5 basil leaves, salt, and pepper. Stir to combine.

Simmer uncovered over medium-low heat for 15 minutes, stirring occasionally, until the sauce thickens and deepens in color. Remove the garlic slices if you prefer a cleaner flavor. Set aside.

Heat the oven to 220 C / 425 F. Bring a large saucepan of water to a rolling boil. Add 1 tbsp salt.

Cook the gnocchi in two batches. Drop them into the water and cook until they float to the surface plus 30 seconds more, about 2 minutes total. They should be slightly underdone at this stage.

Lift the gnocchi out with a slotted spoon, letting a little starchy water cling to them, and transfer directly into the tomato sauce. Gently toss to coat.

Transfer the sauced gnocchi to a shallow baking dish (approximately 30 x 20 cm), spreading them in an even layer.

Arrange the dried mozzarella slices over the top, covering the gnocchi as evenly as possible.

Scatter the grated Parmigiano-Reggiano over the mozzarella. Drizzle with 1 tbsp olive oil.

Bake at 220 C / 425 F for 12 to 15 minutes until the cheese is fully melted and bubbling. Switch to broil for the final 2 minutes until the cheese shows light golden spots.

Remove from the oven and rest for 3 to 4 minutes. Scatter the remaining fresh basil leaves over the top and serve directly from the baking dish.