Prep the croissants: Slice each mini croissant in half horizontally with a serrated knife. If you like, lightly toast the cut sides in a dry skillet or with a little butter for 1–2 minutes until just crisp.

Mix your spread: In a small bowl, stir together mayonnaise and Dijon (about 2 parts mayo to 1 part mustard). Add a pinch of salt and pepper. For a herby note, mix in a bit of pesto or dried oregano.

Layer the base: Spread the mayo-mustard mix on the bottom half of each croissant. Add a lettuce leaf to keep the bread from getting soggy.

Add protein and cheese: Fold a slice or two of turkey or ham so it fits neatly. Top with a small slice of cheese. If using tomato or cucumber, add thin slices now and season lightly with salt and pepper.

Finish and secure: Spread a thin layer of condiment on the top half. Close the sandwich, press gently, and secure with a toothpick if serving on a platter.

Optional warm melt: For a melty version, place assembled sandwiches on a baking sheet and warm in a 300°F (150°C) oven for 5–7 minutes, just until the cheese softens. Add fresh lettuce after heating to keep it crisp.

Serve: Arrange on a platter with pickles or pepperoncini on the side. Serve immediately for the best texture.