Vegetarian Moussaka

Name: Vegetarian Moussaka
Ingredients: 3 medium eggplants (3 to 4 pounds); 1/2 cup extra-virgin olive oil; Kosher salt; 2 cups dried French lentils; Vegetable oil, for frying, plus more for the pan; 4 large russet potatoes, peeled and sliced 1/4 inch thick; 1 1/2 sticks (12 tablespoons) unsalted butter; 1 medium onion, finely chopped; 1 clove garlic, minced; 3 cups tomato puree; 2 tablespoons tomato paste; 1 teaspoon dried oregano; Freshly ground pepper; 1 cinnamon stick, broken into pieces; 2 cups milk; 3 cups heavy cream; 1/4 teaspoon ground nutmeg; 3/4 cup all-purpose flour; 6 large egg yolks; 1 cup crumbled sheep’s milk feta cheese