Spray a skillet with cooking spray and heat over medium.
In a bowl, beat together the eggs, milk, and grated cheese. Season with 1/8 teaspoon salt and pepper; pour into skillet, cook and stir until scrambled and no longer runny.
Mash avocado and season with the remaining salt.
Place tortillas in between two paper towels and heat in the microwave about 30 seconds just until warm.
Spread avocado mixture on one side of each warmed tortilla, add scrambled eggs, then roll into burritos.