Preheat the oven to 200 degrees C (400 F) and line a large baking tray with parchment paper.
Add the butternut squash, bell pepper, carrot and 1 tbsp of the olive oil to a mixing bowl and stir together well. Transfer the vegetables to the baking tray and bake for 25-30 minutes, until fully softened and crispy.
When the vegetables are almost done, start cooking the rigatoni (or any other pasta of your choice) according to packaging instructions.
Transfer the roasted vegetables to a blender together with the silken tofu, red chilli, maple syrup, nutritional yeast, plant based milk, cumin, paprika, garlic powder, turmeric and salt. Blend until smooth.
Heat the rest of the olive oil in a large pan over a medium heat and add the onion. Cook for a minute, then add the tomato paste and cook for 2-3 minutes more, until softened.
Pour the sauce into the pan and add the vegan cheese, together with the spinach. Stir until the spinach wilts.
Drain the pasta and add it to the frying pan, stirring for a few minutes more. Serve with fresh herbs of your choice.
To stop the pasta and spinach going soggy, store/freeze the sauce separately.