Cut the squash in half, scoop out seeds with rounded tablespoon and lightly rub skin with oil (to keep moist during baking).
Place cut side down on flat tray lined with aluminum foil.
Cook in 350º oven about 30 minutes. Cool and remove skin.
Carefully cut 1/3 of one of the halves into 1/4" cubes and set aside in a bowl. Reserve the rest of the squash for other recipes.
While the squash is warm, add 2 TBS chopped onion and gently mix into together.
While the squash is baking, reduce a can of chicken stock down to about 3/4 cup. Add the lentils, 2 TBS chopped onion and bay leaves and cover.
Cook the lentils, stirring occasionally, about 20 minutes (or until tender), adding water as needed.
After the lentils are cooked, remove pan from heat and while the lentils are still warm, stir in 1-2 TBS red wine vinegar and an equal amount of olive oil. Season to taste with salt and white pepper.
Mix warm lentils into the squash cubes, adjusting seasonings (vinegar, olive oil, salt and pepper) to your taste.