A delicious portable take on fondue; bread cups hold the cheese and cornichons top it all off.
Preheat oven to 350 degrees. Roll out bread slices as thinly as possible with a rolling pin. Trim crusts; cut each slice into 4 even squares. Press into bottom and up sides of mini muffin cups. Bake until dry and crisp, 12 to 15 minutes (white bread will take slightly longer than pumpernickel). Let cool completely. Toasted bread cups can be made 1 day ahead and stored in an airtight container at room temperature.
Stir together mayonnaise, Dijon, and brandy. Add cheeses and gently stir to combine. Season with 1/4 teaspoon pepper. Transfer bread cups to a parchment-lined baking sheet. Divide cheese mixture evenly among bread cups (about 1 rounded teaspoon each).
Bake until cheese is melted, bubbly, and golden in places, 8 to 10 minutes. Top with cornichons;serve immediately.
Soft, presliced sandwich bread works best for rolling out flat.