Saute shallot, garlic and oil for a few minutes. Add the tomatoes and season the with salt and pepper - cook on medium heat with cover on for 2-3 minutes. Remove cover and then squash tomatoes slightly with back of fork (or potato masher).  Add the spinach and coat through the tomatoes and juice and let cook until wilted.  Give a squeeze of lemon juice and stir. Transfer to a plate and add the lemon zest and optional grated parmesan cheese.