Preheat oven to 350 degrees.
Thaw spinach in a strainer and pat dry to remove excess water. Set aside.
Heat olive oil in large skillet or sauce pan over medium heat.
Saute onion for 8-10 minutes or until they begin to turn translucent.
Add fresh garlic and saute for an additional minute or until fragrant.
Add spinach, artichoke hearts, sour cream, garlic powder, onion powder, salt, pepper, and cayenne. Stir together and cook over medium heat for 5 minutes.
Pour into an 8x8 or 9 inch baking dish and top with dairy-free mozzarella shreds.
Bake for 20 minutes or until cheese in melted.
Remove from oven and serve warm with toasted baguette or tortilla chips.
Happy Eating!