Prep the croissants: Slice each croissant horizontally. Warm a skillet over medium heat with a thin smear of butter or oil. Place croissants cut-side down and toast until lightly crisp, 1–2 minutes. Remove and set aside.

Beat the eggs: In a bowl, whisk eggs with milk or cream, a pinch of salt, and black pepper. Whisk until the mixture looks smooth and slightly frothy. This helps make the eggs tender.

Cook the eggs low and slow: Add butter to a nonstick skillet over low heat. Pour in the eggs. Stir gently with a spatula, pushing from the edges to the center. Cook until soft and custardy, 3–5 minutes. Take them off the heat while still glossy; they’ll finish setting on the sandwich.

Warm the meat and melt the cheese: If using bacon or ham, warm it briefly in the same skillet. Lay cheese slices over the meat to soften, or place cheese directly on the toasted croissant bottom while it’s still warm to encourage melting.

Spread and layer: Spread a little Dijon or mayo on the croissant tops. On the bottoms, add cheese (if not already there), then the warm eggs. Top with bacon or ham, greens, and tomato slices if using. Add a pinch of salt and pepper over tomatoes and greens.

Finish and serve: Close the sandwich gently. For extra melt, return the assembled sandwiches to the warm skillet, cover for 30–60 seconds, and heat on low. Slice in half if you like, and serve immediately with hot sauce on the side.