In a large bowl, blend together sour cream and cream cheese until thick and smooth.
1/2 cup sour cream, 8 ounces cream cheese
Add spinach, Monterey jack cheese, Parmesan cheese, dried chopped onion, garlic, salt, black pepper, and red pepper flakes to bowl, then stir until thoroughly combined.
10 ounces frozen spinach, 1 cup shredded Monterrey jack cheese, 1 cup shredded Parmesan cheese, 1 tablespoon dried minced onion, 1 tablespoon fresh minced garlic, 1 pinch salt, 1 pinch black pepper, 1 pinch red pepper flakes
Transfer spinach dip to parepared baking dish and smooth it out to an even layer.
Bake spinach dip for 10 minutes or until hot and cheese is melted.
Serve spinach dip immediately with sliced french bread for dipping.