Easy Tomato Sauce

• 5 tbsp olive oil
• 2 onions, finely chopped
• 8 large garlic cloves, peeled

Heat 4 tablespoons of the oil in a large frying pan over a high heat. Reduce the heat to medium, add the onions and fry, stirring, for 5–8 minutes until just starting to turn golden. Add the garlic and fry for a further 1 minute.

Transfer the onions and garlic to the slow cooker and stir in