Mushroom Topping:
3 cups sliced mushrooms
1 garlic clove, minced
1 tablespoon olive oil
1 tablespoon chopped fresh thyme (or 1/2 tablespoon dried thyme)
2 tablespoons dry white wine, such as Chardonnay or Sauvignon Blanc
1/4 teaspoon salt
Ground black pepper, to taste

Risotto:
5 cups vegetable stock (or 4 cups stock plus 1 cup water)*
3 tablespoons olive oil
1/2 cup diced onion
2 cups arborio or carnaroli rice
1/2 cup dry white wine, such as Chardonnay or Sauvignon Blanc
10 ounces fresh spinach, rinsed, stemmed, and chopped (about 10 cups)
1 cup crumbled feta cheese