2 tablespoons extra virgin olive oil
1 small onion, diced
2 cloves garlic, minced
1 small potato, peeled and diced
Kosher salt and freshly ground black pepper
2 (12-ounce) packages frozen artichoke hearts
2 strips lemon zest (optional)
4 cups low sodium vegetable broth
2 cups loosely packed baby spinach
1/2 cup freshly grated parmesan cheese
3/4 cup grated cheddar, mozzarella, or Gruyere
3/4 cup lightly crushed tortilla chips