Meal type: Side Dish / Vegetarian Main
Prep time: 15 minutes
Cook time: 1 hour 10 minutes
Total time: 1 hour 25 minutes
Serves: 4

Overview

Sweet roasted onions meet the deep tang of tamarind and the richness of browned butter in this elegant, flavor-packed dish.
The onions become soft, jammy, and caramelized in the oven, while the tamarind butter glaze adds a perfect balance of tart, savory, and slightly sweet notes. Serve it alongside roasted meats, lentils, or grilled vegetables - or let it shine as a vegetarian centerpiece.

Ingredients

For the Onions

• 4 large yellow or red onions (peeled, halved through the root)

• 2 tbsp olive oil

• Salt and freshly ground black pepper, to taste

For the Tamarind Butter Glaze

• 3 tbsp unsalted butter

• 1½ tbsp tamarind paste (or concentrate)

• 1 tbsp brown sugar or honey

• 1 tsp soy sauce (or tamari)

• ½ tsp ground cumin

• ¼ tsp chili flakes (optional, for a mild kick)

• 1 tbsp water, as needed to thin the glaze

For Garnish

• Fresh cilantro or parsley, finely chopped

• Optional: a drizzle of lemon juice or balsamic reduction

Instructions

Step 1. Prepare the Onions

1.  Preheat your oven to 400°F (200°C).

2.  Trim the onions slightly at the base so they sit flat. Slice in half vertically through the root so each half stays intact.

3.  Place them cut-side up in a baking dish or roasting pan.

4.  Drizzle with olive oil and season generously with salt and pepper.

5.  Cover the dish with foil and bake for 35 - 40 minutes, until the onions begin to soften.

Step 2. Make the Tamarind Butter

1.  While the onions bake, melt the butter in a small saucepan over medium heat until it starts to foam and turn golden brown (about 3–4 minutes).

2.  Reduce the heat to low and whisk in the tamarind paste, brown sugar, soy sauce, cumin, and chili flakes.

3.  Add a splash of water if the mixture seems too thick — it should have a syrupy consistency.

4.  Taste and adjust - it should be tangy, slightly sweet, and buttery.

Step 3. Glaze and Roast

1. Remove the foil from the onions. Spoon or brush the tamarind butter generously over each onion half.

2. Return to the oven uncovered and roast for another 25–30 minutes, basting occasionally with the glaze.

3. The onions are done when they are deeply golden, soft all the way through, and glossy with tamarind caramelization.

Step 4. Serve

1.  Transfer the onions to a serving platter.

2.  Spoon any remaining tamarind butter from the pan over the top.

3.  Sprinkle with fresh herbs and finish with a drizzle of lemon juice or balsamic glaze for brightness.

Serving Suggestions

• Serve warm as a side dish with roasted chicken, lamb, or grilled tofu.

• Layer them over creamy mashed potatoes, polenta, or risotto for a luxurious vegetarian main.

• Slice and toss into grain bowls with lentils or quinoa for a balanced meal.

Tips & Variations

• Make it vegan: Substitute butter with vegan butter or coconut oil.

• Add depth: A splash of pomegranate molasses or Worcestershire sauce enhances the umami flavor.

• Spicy version: Add a pinch of cayenne or smoked paprika to the glaze.

• Extra caramelization: Broil for the last 3 minutes for a slightly charred, glossy finish.

Nutrition (per serving)

(approximate values)

• Calories: 180 kcal

• Fat: 11 g

• Carbohydrates: 19 g

• Protein: 2 g

• Fiber: 3 g

Chef’s Note

Tamarind-Butter Baked Onions embody a perfect flavor trifecta - sweet, sour, and savory.
The natural sugars in the onions caramelize beautifully, while the tamarind’s tangy acidity cuts through the richness of the butter.
The result? A dish that feels both comforting and exotic - rustic enough for a family meal, yet refined enough for a dinner party.