Roll out the pie dough very thinly. Use a small glass to cut out rounds. Place each dough round into the wells of a mini muffin or tart pan (no need to grease if using silicone). Press the dough firmly into the bottom and sides. Place ceramic baking weights (for blind baking) on the dough. Refrigerate for 30 minutes. Bring the butter to room temperature. Rinse the snails and place them in a strainer.

Finely chop the parsley. Peel and press the garlic cloves. In a bowl, combine the garlic, parsley, and softened butter. Mix until smooth. Add black pepper to taste.

Place a little garlic butter in each pastry cup, add a snail, then top with more garlic butter. Arrange the filled cups on a baking sheet lined with parchment paper. Bake for about 10 minutes, until the butter is bubbling—watch closely at the end of baking.