Preheat oven to 300° F. Line a sheet pan with a silicone mat or parchment paper and set aside.

Prep ingredients: Crush garlic, dice onion. Cut tomatoes in half and remove the seeds and watery bits from each tomato. Measure out spices and chop herbs.

In a small microwave-safe bowl, add olive oil and onion and stir until mixed. Microwave on high heat for 30 seconds. After removing bowl from microwave, give it a good stir.

In a large mixing bowl, add all the prepared tomatoes. Toss the tomatoes with the oil and onion mixture. Add the spices and mix until tomatoes are well coated.

Add the seasoned tomatoes to the sheet pan, cut side up. Drizzle over any remaining oil and onion mixture. Sprinkle on the chopped herbs.

Roast for 2 hours. After 2 hours, increase the heat to 400° F and roast for an additional 30 minutes or until tomatoes are caramelized along the edges and there’s a few dark spots throughout.

Remove from oven, and scrape the tomatoes and any browned bits into the food processor, along with the balsamic glaze. Pulse a few times until you get a nice chunky sauce. If you’d like it smoother, keep processing until you like the texture.