Grandma’s Onion Pie
Oh, you’re in for a treat! This isn’t just any pie – it’s that magical dish that makes everyone at the table suddenly quiet down as they savor each bite. Grandma’s Onion Pie transforms humble onions into something so deliciously savory that you’ll wonder why you ever relegated onions to supporting roles in your cooking.

The beauty of this pie lies in its perfect simplicity. Sweet, caramelized onions blend with eggs and Parmesan to create a custard-like texture that’s both light and satisfying. It’s like a crustless quiche that lets the onion flavor shine through in every forkful. Trust me, even the “I don’t like onions” folks will be asking for seconds.

Ingredients

For the filling:
- 6 to 8 medium onions, thinly sliced
- 2 tablespoons canola oil
- 6 large eggs
- 1 cup soft bread crumbs
- 1/2 cup grated Parmesan cheese
- 1/2 cup minced fresh parsley

Steps

- Preheat your oven to 350°F (175°C) and position a rack in the center. Grease a 10-inch pie plate generously to prevent sticking, as this crustless pie needs good coverage.
- In a large skillet over medium heat, add the 2 tablespoons of canola oil. Once shimmering (but not smoking), add your thinly sliced onions. Sauté the onions for 8-10 minutes until they become translucent and soft. Watch carefully – you want them soft but not browned, as browning will create a different flavor profile than the sweet, mild taste we’re aiming for.
- Transfer the cooked onions to a colander set over a bowl and allow to drain thoroughly for 5 minutes. Excess moisture will make your pie soggy, so don’t skip this step. Gently press with a paper towel if needed to remove additional moisture.
- In a large mixing bowl, vigorously whisk the 6 eggs until they’re well beaten and slightly frothy, about 30 seconds of continuous whisking. This aeration helps create a lighter texture in the finished pie.
- Add the 1 cup of soft bread crumbs, 1/2 cup grated Parmesan cheese, and 1/2 cup minced fresh parsley to the whisked eggs. Stir until just combined – overmixing at this stage can make the final texture tough.
- Fold in the drained onions gently, making sure they’re evenly distributed throughout the egg mixture. The mixture should look quite onion-heavy – this is correct! The eggs will puff and rise during baking.
- Pour the mixture into your prepared pie plate, spreading it evenly with a spatula. The filling should come about 3/4 of the way up the sides of the dish.
- Bake in the preheated oven for 35-40 minutes. You’ll know it’s done when the center is set and no longer jiggles when gently shaken, and a knife inserted into the center comes out clean without any wet egg mixture attached. The top should be lightly golden but not browned.
- Allow the pie to rest for 10 minutes before slicing. This resting time is crucial as it allows the eggs to fully set and makes for cleaner slices.

Smart Swaps
- Use olive oil instead of canola oil for a more Mediterranean flavor profile
- Substitute whole wheat bread crumbs for regular bread crumbs to add more fiber (1:1 ratio)
- Replace 1/4 cup of the Parmesan with sharp cheddar for a different flavor dimension
- Add 2 tablespoons of fresh thyme or rosemary along with the parsley for an herbal accent
Make It Diabetes-Friendly
- Use 1 cup of almond flour instead of bread crumbs to reduce carbs by approximately 15g per serving
- Add 1/2 cup of finely chopped bell peppers to increase fiber content while adding color and nutrients
- Serve smaller portions (1/10 of the pie instead of 1/8) alongside a mixed green salad dressed with olive oil and vinegar to reduce the glycemic impact
- For extra protein without added carbs, add 1/4 cup cooked and crumbled turkey bacon to the filling
Pro Tips
- Slice onions to an even 1/8-inch thickness for consistent cooking
- Chill the pie for 30 minutes after baking for cleaner, more defined slices if serving for a special occasion
- If you notice the top browning too quickly, loosely cover with foil after about 25 minutes of baking
- This pie reheats beautifully at 325°F (165°C) for 10-15 minutes, making it perfect for make-ahead meals