Spinach Pesto

I like pesto made with basil, but that wonderfully, fresh, aromatic herb is so expensive and I have not the patience to grow it myself.  While I made this recipe 2-3 times at work, I adapted it for home.

Ingredients

1/2 cup toasted pine nuts or walnuts (optional)
2 large garlic cloves
4 cups tightly packed fresh spinach
1/2 cup fresh grated Parmesan cheese
(or nutritional yeast if you're vegan)
1/2 to 3/4 cup extra virgin Olive oil
TT - Salt
TT - Pepper

Water, as needed

Instructions:

Place all ingredients, except oil, in a food processor or blender and blend until combined but still containing some texture.

With the blender/processor still running, drizzle the oil in slowly and blend until smooth.  Add water to thin the mixture if it's too thick - spinach pesto will be thick.  Adjust seasonings and refrigerate.