Preheat oven to 190°C fan bake
Cut pumpkin in half & on the rounded bum of each half, slice off a small bit
Scoop out seeds & place on oven tray with baking paper
Divide butter & garlic between two halves
Season with salt & pepper, cover with foil
Drizzle onion halves with olive oil & wrap with foil
Roast for 1 hour & 15 mins or cooked, scoop out pumpkin flesh & butter, add to saucepan
Add onions to saucepan with stock, cook over medium heat with lid for 40 mins
Remove from heat, add cream & peppers, salt to taste
Once cooked a little, blend with stick blender until smooth