High Protein Breakfast Quesadilla

Name: High-Protein Breakfast Quesadilla
Ingredients: 1 large egg; 2 large egg whites; Kosher salt and freshly ground black pepper; 2 teaspoons unsalted butter; 2 ounces sliced Canadian bacon, chopped; 1 baby bell pepper, thinly sliced crosswise; 1 cup loosely packed baby spinach; One 8-inch flour tortilla (soft taco size), preferably a higher protein type; 1/4 cup shredded mild Cheddar; Hot sauce or salsa, optional, for serving