Spanakorizo (Greek Spinach and Rice)

Name: Spanakorizo (Greek Spinach and Rice)
Prep time: 10 min
Cook time: 20 min
Total time: 30 min
Cuisine: Greek
Ingredients: 1/4 cup extra-virgin olive oil; 1 bunch green onions (thinly sliced, 1/2 cup dark green tops reserved (about 8-10 green onions) ); 8-10 oz. baby spinach ((see notes for other greens)); 1 cup basmati rice ((or other long grain white rice or parboiled rice)); 2 cups vegetable broth (or water, or chicken broth); 1/2 teaspoon kosher salt (plus more if needed); 1/4 cup fresh chopped dill (or mint, parsley, or a combination); juice and zest of 1 lemon ((about 1 teaspoon zest and 2 tablespoons juice)); fresh cracked pepper, crumbled feta cheese, plus extra olive oil and chopped fresh herbs (for serving, optional)