Step 1

Heat oil in a medium sauce pan until shimmering. Add onions and cook until softened, but not browned, about 5 to 7 minutes. Add in carrot and celery and cook until softened, about 3 to 5 minutes. Add in garlic and cook until fragrant, about 30 seconds.

Step 2

Add in tomatoes, oregano, and crushed red pepper, stir to combine, and bring to boil. Reduce to a simmer and cook until slightly thickened, about 30 minutes, stirring occasionally.

Step 3

Remove from heat, stir in basil, and season with salt and pepper to taste. Use immediately or let cool to room temperature and store in an airtight container in refrigerator for up to a week, or freeze up to 6 months.