Preheat oven to 400 degrees and line a baking sheet with parchment paper.
Slice the Roma tomatoes lengthwise and gently toss in 1/4 cup olive oil and season with salt and pepper.
Place tomatoes onto the baking sheet and bake for 45 minutes.
In a large stock pot or dutch oven, heat the 2 Tbsp. of oil and butter on medium heat. Once butter has melted add the onion, garlic and red pepper flakes. Saute until onions are translucent and close to browning, about 10 minutes.
Pour in chicken broth, roasted tomatoes, canned tomatoes and juice, basil leaves, thyme and salt and pepper. Bring to a boil and continues to simmer for 40-45 minutes, uncovered.
Remove from heat and use an emulsion blender to puree the soup. You can also pour small batches at a time into a regular blender if you do not own an emulsion blender. Blender until smooth. Serve each bowl with a splash of heavy cream and fresh parmesan - optional.