In a large pot at medium-high heat, add the olive oil and carrots to the pot. Cook the carrots for about 10 minutes until they start to brown slightly.
2. Step
Next add the chopped onion, red bell pepper, celery, garlic, oregano, basil, salt, and pepper to the pot and cook until the vegetables are caramelized and tender.
3. Step
Add the tomato paste, stir it into the vegetables, and allow the tomato paste to brown deeply. It should be very aromatic before moving forward.
4. Step
Add the canned tomatoes and water, bring the sauce to a boil, and then reduce to a simmer. Simmer the sauce for at least 1 hour.
5. Step
Add the sauce to a blender in batches or use an immersion blender to puree the sauce to your desired consistency.
6. Step
Let the sauce cool completely and then pour the sauce into freezer-safe bags. Place the bags into a leak-proof container/tray, and freeze for up to one month.
7. Step
Reheat the frozen sauce with ½ cup (120 ml) of water in a pot until it comes to a boil and then use as desired.
