Bean, tomato and chorizo soup

Ingredients

• 1 cup dried three-bean mix, soaked overnight
• 1 tbsp olive oil
• 1 medium onion, diced
• 100 g chorizo, sliced thickly
• 400 g can crushed tomatoes
• 1 tsp smoked paprika
• 2-3 cups water or vegetable stock
• Salt and pepper, to season
• Store-bought pesto, to serve
• Parmesan cheese, grated, to serve