Preheat your oven to 375°F (190°C).
In a mixing bowl, combine the eggs, heavy cream, garlic powder, and cayenne pepper, whisking until smooth and frothy.
Heat olive oil in a skillet over medium heat, then pour in the egg mixture.
Cook gently, stirring occasionally, until the eggs are fluffy and just set, about 5 minutes. Remove from the heat and let cool slightly.
Carefully slice each croissant in half lengthwise.
On the bottom half of each croissant, place a piece of bacon or a sausage link, followed by a generous portion of the scrambled eggs, a handful of mozzarella cheese, and a few leaves of fresh basil or mixed greens if desired.
Cap each sandwich with the top half of the croissant.
Arrange the sandwiches on a baking sheet and bake for 8-10 minutes, or until the cheese is bubbly and the croissants are golden.
Serve warm and relish this delightful breakfast treat!