Cut the butternut squash, remove seeds, peel, and chop into bite-sized pieces. Slice the onion thinly.

Heat butter in a pot over low heat, add onions and sauté until softened. Add the squash and stir until coated. Add water, bring to a boil, cover, and simmer for 8–10 minutes until squash is tender. Let cool slightly.

Blend the cooked squash and onion mixture in a blender until smooth.

Return the blended mixture to the pot, add milk, consomme, salt, and pepper. Heat over medium heat until warmed through.