There’s no spinach in the list of ingredients. How much?

PS. The mushrooms are missing too. Again use about 3/4 cup cooked.
And, given the two omissions compare tested recipe(s) by trusted authors elsewhere just to be sure you've got a complete version.

Hi Jeannie! I can't speak for the author, but—looking at the recipe's other ingredients—I'd say that about 3/4 cup of chopped, cooked spinach would work well in this case. You could start with about 1/2 cup, mix together all the ingredients, then add more to sight. Hope this helps!