Overnight marinated red onions are simple to make, and look elegant when served on a fancy platter. The secret ingredient is time, so make sure to allow enough time for the onions to marinate overnight.
This recipe is a huge hit with my three girls. Honestly, who doesn’t love the smell of onions roasting in the oven on a cold January day? I recommend using red onions as they are sweeter and prettier than their yellow cousins. If you choose to use both, just note that the red onions cook faster. Keep the skins on while the onions marinate and bake as it help them keep their shape, but remove them before serving. For best flavor, marinate and roast the onions with the flat side down in the marinade, and then turn them over half way through. Spooning the marinade over the onions while cooking also helps maximize the flavor.
This tasty marinade comes together super fast, and the onions prep in a flash. Really, what’s not to like? Experience something new, and give it a try this week. Serve this along side our easy turkey with mushroom gravy.Print
Overnight marinated red onions is a healthy, low carb recipe for oven baked onions flavored with two vinegars, brown sugar, fresh rosemary, salt, pepper, and butter.
For the Marinade
- 1 cup filtered water
- 1/2 cup sherry vinegar
- 1/2 cup white balsamic vinegar
- 2 tablespoons brown sugar
- 1 heaping teaspoon fresh rosemary, chopped
- 1/2 teaspoon salt
- 1/8 teaspoon black pepper
For the Roasted Onions
- 4 large red onions, halved with skins on
- 2 tablespoons butter
- 1 teaspoon fresh rosemary, chopped
- a few grinds of black pepper
- Cut the ends off each of the four red onions, then halve them. Keep the skins on, as it helps the onions keep their shape. Place the onions flat side down in a baking pan with sides.
- Pour the water and the vinegars in a bowl, then add the brown sugar and spices. Stir well, and then pour over the onions. Cover with foil and allow to marinate for a minimum of 12 hours.
- Cook uncovered at 400 F for 30 minutes. Flip each onion over. Put a pat of butter on top of each onion and sprinkle the rosemary and a few grinds of black pepper over top.
- Place back in the oven and cook for 15 minutes more, then take out the pan and baste the onions with the marinade. Repeat this process after 1 hour of cooking and then again at 1 hour 15 minutes.
- Remove the tough outer skins before serving. Serve warm on a pretty platter. Pour the warm marinade from the baking pan into a small bowl and place this on your dinner table for your guests to spoon over their onions.
- This is best made the night before you want to cook it. The prep time is minimal but the chilling time of 12 hours is necessary for maximum flavor.