Spanakopita Latkes

Name: Spanakopita Latkes
Ingredients: 1 1/2 pounds Yukon Gold or Russet Potatoes, peeled; 1/2 large yellow onion, grated and excess water squeezed out; 1 cup crumbled feta cheese; 9 ounces package frozen spinach, thawed and excess water squeezed out; 1 1/2 tablespoons all-purpose flour; 1 large egg; 1 teaspoon kosher salt; fresh black pepper; canola oil, for frying; flakey sea salt; tzatziki or sour cream, to serve