Preheat oven to 350 degrees F.
Into a medium-sized skillet, heat oil over medium-high heat. Add shallots and cook 3 minutes, stirring occasionally, until softened and lightly caramelized.
Into a food processor, add shallots, tofu, sour cream, juice, powder, salt, and pepper. Blend on high until combined and consistency is smooth.
Add the mixture to cooked fusilli pasta and toss well to coat. Stir in reserved pasta-cooking water and spinach.
Onto a prepared 9” x 13” baking dish, add noodles in an even layer. Bake uncovered for 30 minutes. Serve warm or at room temperature.