Begin by cutting the acorn squash in half and scooping out the seeds and stringy flesh in the middle. Place the halves face down on a baking sheet lined with parchment paper and bake in a 400 degree oven for 20-25 minutes or until mostly soft when poked with a sharp knife. You still want a little give. When cool enough to handle, scoop the flesh out of the skins.While the squash is baking, dice the onion and apple, mince the garlic, and grate the ginger.Heat the olive oil in a large pot or dutch oven. Add the onions, garlic, and ginger. Cook for about 5 minutes or until onions or soft, stirring occasionally. Add the apple, red curry paste, and turmeric. Cook for another minute or so, stirring to evenly distribute the chili paste.Add the squash, broth, coconut milk, and salt, bringing the soup to a boil and then reducing to a low simmer. Simmer for 15 minutes or until the apples and squash are soft enough to smash with the back of a spoon. Using an immersion blender (or regular blender), blend the soup until it's uniformly creamy. Stir in the sambal oelek. Taste and adjust the salt.Serve topped with veggies of your choosing.