Preheat your oven to 375°F.
In a large mixing bowl, combine the chopped spinach, ricotta cheese, mozzarella cheese, Parmesan cheese, egg, garlic powder, salt, and black pepper. Mix until well combined.
Unroll the crescent roll dough on a lightly floured surface. Pinch the seams together to create a solid sheet of dough.
Spread the spinach and cheese mixture evenly over the dough, leaving a small border around the edges.
Starting from one end, carefully roll the dough into a log shape. Slice the log into 1-inch pieces and place them on a baking sheet lined with parchment paper.
Bake in the preheated oven for 15-20 minutes, or until the rolls are golden brown and puffed up.
Serve warm with marinara sauce for dipping.