INGREDIENTS
1 tbsp
olive oil
3
onions (, medium or large, sliced)
salt
1 tbsp
balsamic vinegar
1 tbsp
olive oil
8 oz
mushrooms (, sliced (such as button mushrooms, shiitake, etc.))
3
garlic cloves (, minced)
salt
6 oz
spinach (, fresh)
1/3 cup
heavy cream
1/4 cup
milk
1/2 cup
Parmesan cheese (shredded)
1/4 tsp
salt