In a large skillet, heat olive oil over medium heat. Add the chopped onion and cook until translucent, about 5 minutes.
Stir in the minced garlic and continue to sauté for an additional minute until fragrant.
Add the sliced eggplant to the skillet, season with salt, pepper, dried oregano, and cook until the eggplant is tender, about 10 minutes. Remove from heat and let cool slightly.
Spread the ricotta cheese evenly across the bottom of the pie crust.
Layer half of the cooked eggplant mixture over the ricotta.
Add a layer of tomato slices on top of the eggplant, followed by half of the mozzarella cheese.
Repeat the layers with the remaining eggplant, tomatoes, and finish with the remaining mozzarella.
Sprinkle fresh basil on top before placing in the oven.
Bake for 35-40 minutes or until the top is golden and bubbly.
Remove from the oven and let it cool for about 10 minutes before slicing into wedges.
Notes
Serve warm on a rustic wooden board, garnished with a sprig of fresh basil on each slice for a pop of color.