Gather all ingredients.

Preheat the oven to 350 degrees F (175 degrees C).

Place squash halves, cut-side down, on a baking sheet. Bake in the preheated oven until flesh begins to soften, about 30 to 45 minutes.

Remove squash from the oven and transfer one squash half, cut-side up, to a deep baking dish. Spoon butter and brown sugar into the cavity. Place remaining squash half, cut-side down, over top to seal.

Return to the oven and continue to bake until flesh is soft, 30 minutes.

Serve hot and enjoy!