Preheat the oven to 180C/350F fan or 200C/400F conventional.
Cut the squash in half and remove the seeds. Cut the squash into quarters and trim off the skin using a knife. Chop the squash into medium-sized cubes and place in a baking tray.
Add the 2 garlic cloves (skins on), remove the rosemary from the sprigs and add it to the tray with a good pinch of salt and pepper. Drizzle over 2-3 tablespoons of olive oil and toss so everything is coated. Roast in the oven for around 35-40 minutes, until cooked through.
While the squash is cooking, make the crispy sage leaves.
Heat 1 tablespoon of olive oil in a pan. Once hot, add the sage leaves and fry them for 1-2 minutes on each side. Transfer them to a plate lined with kitchen paper to drain. Set aside.
Once cooked, blitz the squash with garlic (skins removed), rosemary, heavy cream and Parmigiano cheese until smooth using a food processor or blender (I did this in a bowl with an immersion blender). Taste for seasoning and add more salt if needed.
Transfer the squash sauce to a large pan and bring a large pot of water to a boil.
Meanwhile, add the heavy cream and taleggio to a separate saucepan over medium-low heat until the cheese has melted and the cream has thickened slightly. Keep the taleggio sauce on a low heat, stirring occasionally while you cook the gnocchi.
Add the gnocchi to the boiling water and cook until they float to the surface. At the same time, heat the squash sauce over medium heat and add around ½ cup/120ml of pasta water to loosen it to a saucy consistency,
Transfer the gnocchi to the sauce and stir until well coated. Add more pasta water if needed.
Serve the gnocchi in bowls, drizzle over the taleggio cream, then top with crispy sage and serve.
Notes
Prep in advance: you can prepare the butternut squash sauce in advance and store it in the fridge for up to 3 days. Add it to a pan and loosen it with pasta water when ready to serve. The taleggio cream is best served immediately.