Cook the red lentil pasta according to the packet instructions. Before draining, reserve a small mug of the pasta cooking water, then set the pasta aside.
Finely chop or crush the garlic and thinly slice the red onion.
Heat the olive oil in a large frying pan over a medium heat. Add the garlic and red onion and cook for 4–5 minutes until softened.
Add the cherry tomatoes and cook for a further 3–4 minutes until they begin to soften and release their juices.
Stir in the oregano, basil, and chilli flakes and cook for 1 minute until fragrant.
Pour in the passata and stir through the crème fraîche. Allow the sauce to simmer gently for 5–7 minutes until slightly thickened.
Add the spinach and cheddar cheese, stirring until the spinach has wilted and the cheese has melted into the sauce.
Season with black pepper to taste and add a little salt if required.
Add the cooked pasta to the sauce along with a splash of the reserved pasta water. Stir well until the pasta is evenly coated in the creamy tomato sauce.
Serve immediately and enjoy.