Heat butter and olive oil in a large skillet over medium heat. Stir in onion and garlic; cook until soft and translucent, but not brown. Add spinach; cook, stirring frequently, until wilted.
Place tofu, milk, cheese, garlic powder, salt, and pepper in a blender, and puree until smooth.
Stir pureed tofu into spinach. Cook until warmed through. Adjust seasonings, if desired, and serve.
