Preheat your oven to 375 F. Place the squash, cut side up, in a foil or parchment lined baking dish. Spray the squash on both sides with your oil spray, or use your hands to lightly rub/coat the squash with your cooking oil. Bake for 40-45 minutes, or until the edges of the squash are golden and the squash is tender when pierced with a fork.
While the squash cooks, heat the oil in a large, roomy skillet over medium heat. Add the shallots and garlic. Cook for 3 minutes, or until the shallots are tender and clear. Stir in the beans. Next, stir in the collard greens. Cook, stirring often, until the collard greens are tender (about 5 minutes). Add the lemon juice and salt and pepper. Taste and adjust seasoning as desired.
To serve, stuff each squash half with the bean mixture. Top with a sprinkle of vegan parmesan, if desired.