Preheat oven to 350 degrees F and grease a 24-cup mini muffin tin or 2 12-cup mini muffin tins.
Place all ingredients for the crust in a blender and pulse until mixed and can be formed into a dough. Add a little bit more coconut oil if the dough seems too dry.
Knead the dough a few times, then divide it equally into the muffin tin cups. Use your hands to press the dough to the bottom and the sides to form a shell.
Bake for 5 minutes. Remove from the oven and let cool for 5 minutes.
Drain the cashews, and squeeze out the liquid from the artichoke hearts and thawed spinach.
Place cashews, garlic, coconut milk, lemon juice, nutritional yeast, onion powder, sea salt, ground black pepper, and cayenne pepper (if using) in a blender, and blend until smooth and creamy.
Stir in spinach and artichoke hearts to the creamy cashew mixture.
Spoon the filling mixture evenly into the baked dough, about 1 rounded teaspoon per each dough cup.
Bake for 15-20 minutes until the dough is golden and the top of the filling starts to brown.
Remove from oven and cool for 5-10 minutes before digging in.