Preheat oven to 400°F (200°C) and line a baking sheet with parchment paper.
Place grated zucchini in a strainer over the sink or a bowl. Sprinkle lightly with salt and let sit for about 20 minutes to release moisture.
Squeeze out as much excess water from the zucchini as possible using a clean towel or cheesecloth.
In a large bowl, combine the drained zucchini, almond flour, shredded cheese, egg, garlic powder, and black pepper. Mix well to form a cohesive mixture.
Scoop 1/4-cup portions of the mixture onto the prepared baking sheet. Press each portion down to form circles about 1/8 inch thick.
Bake for 25 minutes or until the shells are golden brown and crisp around the edges.
Remove from oven and allow to cool slightly before filling with desired toppings.