In a medium saute pan, add the olive oil over medium heat. Mince the remaining garlic clove and add to the hot oil. Saute for 30 seconds, then pour in the sauce from the blender. Mix well with a spatula and let cook on medium heat about 5 minutes--it should be lightly bubbling, stir frequently. Add in the pesto and red pepper flakes, if using. Stir well to combine and let cook for another 5 minutes to fully combine and thicken.