Preheat oven to 350 degrees.
Slice heirloom tomatoes into large wedges. Add to roasting pan.
To the tomatoes add two whole peeled garlic cloves and sprinkle with salt.
Roast in the oven for approx 1 hour or until tomatoes are soft and have released their juices.
In a medium saucepan, heat a glug of olive oil. Add chili flakes and chopped yellow onion. Sautee until onions are translucent.
Once the tomatoes are done roasting, add them to the saucepan and stir to incorporate.
Blend in a high-speed blender or with an immersion blender until creamy smooth.
Serve warm with crusty bread, grilled cheese or whatever else makes you happy.
