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Slow Cooker Tomato Sauce

Recipe from veganrecipebowl.com
Prep Time15 mins
Cook Time4 hrs
Total Time4 hrs 15 mins
Course: Sauce
Cuisine: Italian
Keyword: vegan
Servings: 5
Calories: 175kcal


  • 2 tablespoons olive oil
  • 2 medium onions, red or white (peeled and finely diced)
  • 4-6 cloves garlic (peeled and minced)
  • 1/4 teaspoon ground black pepper
  • 4 x 400 g cans of chopped tomatoes
  • 1 teaspoon dark brown sugar (level)
  • 1 tablespoon finely chopped oregano (alternatively, 1 teaspoon dried)


  • Set the slow cooker to 110 °C / 230 °F (if it has low / medium / high settings consult your manual to determine the closest setting).
  • When the slow cooker is heated, add the olive oil, onions, garlic and black pepper. The aim is to gently cook with stirring for around 5 minutes, just to take away the raw aroma and taste but not to brown them.
  • Soon as the onions are cooked add the chopped tomatoes, oregano and brown sugar. Stir through to mix everything evenly. Place the lid on (make sure it's on properly to avoid drying out) and leave to cook - no further stirring is needed - for 4 hours.


Slow cookers provide a consistent cooking method which allow for recipes to be made again and again without needing to watch the pot. However, there are differences between each model, so you need to learn how a recipe behaves in your particular slow cooker before you can leave it unattended for the entire cooking time.
The first time you make this sauce, check periodically to ensure it isn't cooking too fast or drying out. Steady, gentle bubbling with the steam condensing and returning to the pot is the aim. Once you find the correct setting to cook this sauce - without drying out - for four hours, the recipe is easy to replicate without needing to check the pot until the time is up.
This sauce keeps well when covered in the fridge for up to four days. It can be frozen for up to four weeks.