Add olive oil to a large stockpot and sauté the chopped onion for a few minutes until it begins to soften and brown slightly.
Add peppers, zucchini, garlic, and tomatoes. Since the sauce will be blended, it can be roughly chopped
Add herbs, salt, and pepper to taste
Stir in rinsed red lentils, they will cook down with the sauce and absorb some liquid
Bring pot to a gentle boil
Reduce heat and allow to simmer for an hour, stirring occasionally
Allow the sauce to cool completely before transferring to freezer containers
Portion the sauce into freezer safe bags or wide mouth glass jars. Leave 2 inches of head space in jars
Thaw the sauce when you're ready to use and enjoy