In a large roasting tray, combine the red pepper chunks, sliced shallots, and garlic. Ensure the vegetables are spread out in a single layer for even roasting.
Season the Vegetables:
Sprinkle the brown sugar and drizzle the balsamic vinegar evenly over the vegetables.
Remove the leaves from the thyme sprigs and scatter them over the mixture. Season generously with salt and black pepper.
Roast the Vegetables:
Place the tray in the preheated oven and roast for about 20-25 minutes. The peppers should start to char slightly, and the sugars in the vinegar and brown sugar should begin to caramelize.
Blend the Sauce:
Transfer the roasted vegetables and any juices from the tray into a blender. Blend on high until the mixture is completely smooth. Taste and adjust seasoning if necessary.
Strain (Optional):
For an ultra-smooth texture, strain the sauce through a fine mesh sieve.
Notes
Consistency Adjustment: If the sauce is too thick after blending, thin it out with a little water or additional balsamic vinegar to achieve your desired consistency.
Storage Tips: This sauce can be stored in an airtight container in the refrigerator for up to a week or frozen for up to 3 months. Reheat gently on the stove or in the microwave.
Serving Suggestions: This versatile sauce can be used as a pasta sauce, a topping for grilled meats, a unique pizza sauce, or as a dip for crusty bread.