Step 1

Coat cubed butternut squash in 1 tbsp of olive oil and season with salt. Bake in a hot oven (225º C / 435º F) for about 40-50 minutes, until butternut squash turns soft and gets lightly caramelised.

Step 2

Heat up 2 tbsp of olive oil in a pan. Fry off garlic gently on a low-medium heat, stirring frequently so it doesn't burn. Add chilli flakes and cook for another minute or two stirring frequently.

Step 3

Cook spaghetti for a minute shorter than you would normally.

Step 4

Mash half the butternut squash with a fork or potato masher (you can also use a food processor or blender for a smoother texture). Put both mashed and whole butternut squash chunks into the pan with chilli and garlic.

Step 5

Add drained pasta and washed spinach into the pan. Incorporate them well into the pumpkin. Taste and season with pepper, a squeeze of lemon juice and additional salt and chilli if needed.

Step 6

Serve immediately with chopped walnuts and lemon zest on top.