Preheat oven to 400°
Line a baking sheet with parchment paper.
Mix the ricotta cheese with the egg, garlic, salt, and pepper.
Roll out the pie crust to about 12-14".
Spread the ricotta cheese mixture around the pie crust avoiding the outer 2-3 inches.
Top with mozzarella cheese,
Pile on the spinach.
Fold the crust over the filling around the edges about 2 inches.
Place the feta cheese on top.
Bake at 400° for 25-28 minutes or until the bottom crust is firm, cooked well, and golden.
Remove from oven, allow the galette to cool for at least 10 minutes before slicing, this will allow the cheese to set up nicely.