Preheat oven to 190℃.
Slice pumpkin into 1 cm (⅓") slices, discarding skin and seeds - see notes for my handy tips for easy peeling.
Arrange pumpkin slices in a baking dish, overlapping slightly to create ridges for the crumble to sit on (see notes).
1 kg butternut pumpkin
Combine fresh sage, mustards, garlic and salt in a medium jug and mix, then add 1-2 tablespoon of cream to mustard mixture, stirring to combine, then add remaining cream and mix well.
300 ml pure cream, 1 teaspoon finely chopped fresh sage, 2 teaspoon wholegrain mustard, 1 teaspoon dijon mustard, 3 garlic cloves, pinch fine salt
Pour cream mixture over pumpkin in prepared baking dish, pouring to coat from the top down on each slice of pumpkin - cover with aluminium foil and bake for 40 mins.
Meanwhile, to make the crumble - place the bacon, breadcrumbs and parmesan in a small bowl, mix well to combine.
⅓ cup day old bread crumbs, 2 bacon rashers, 20 g grated parmesan
Remove pumpkin from oven, carefully lift off foil (steam will escape) and using a small spoon, ladle over some of the excess cream mixture to coat the pumpkin.
Sprinkle the crumble mixture over the pumpkin slices, particularly on the ridges or steps between the slices and any high spots.
Bake for 15 mins uncovered and serve immediately.