Lightly coat a 9-by-13-inch baking pan with oil, making sure to include the sides well. Line the baking pan with parchment paper with overhang on at least two sides and lightly coat the parchment paper with oil. Heat the oven to 375 degrees with the rack in the center position.
1 Tbsp Olive oil
In a large skillet, heat some oil over medium heat. Add the onion and cook, stirring frequently, until golden, 8 to 10 minutes.
1 ea Yellow onion, chopped
Sprinkle with a little salt, add the sun-dried tomatoes and cook for 2 minutes, stirring frequently.
1/4 cup Sun-dried tomatoes, finely chopped
Add the spinach, in batches if necessary, and cook, stirring frequently, just until wilted. (You don’t want the spinach to release any liquid.) Season with salt and pepper, keeping in mind you will also season the eggs. Remove from the heat.
6 oz Baby spinach
Add the eggs to a large bowl, season with 1 teaspoon salt and ¼ teaspoon pepper, and beat with a whisk or a fork until combined. Add the spinach mixture to the eggs and mix to combine.
10 ea Large eggs
Transfer the egg mixture to the baking pan, spreading it out evenly. Top with the feta cheese and bake until the eggs are fully set and the cheese is melted, 10 to 15 minutes. Remove from the oven and allow to rest for 2 minutes.
1/2 cup Feta cheese, crumbled
Slide the frittata onto the cutting board. Slice the frittata width-wise into 5 equal rectangles (each about 2½ inches wide). Place a tortilla on a work surface and spread with cream cheese or goat cheese. Place a slice of frittata on the burrito, leaving a 2-inch border from the bottom. Bring the sides of the burrito in and then fold up the bottom, rolling up the burrito. Repeat with the remaining burritos and frittata.
5 ea Tortillas, burrito size, 3 Tbsp Cream cheese
Heat the same skillet over medium. Lightly coat with oil each wrap on both sides. Place seam side down on the pan and cook until the wrap is warmed through and slightly golden on each side, 3 to 4 minutes per side. Slice in half, on the diagonal if you like, and serve. (To make ahead, wrap the pan-cooked egg wraps in foil and keep in the fridge for 3 days, or the freezer for 3 months. Reheat in the microwave, in a skillet over low heat, or in the oven at 350 degrees.)