Preheat oven to 400 degrees. Cut butternut squash in half lengthwise, scoop out guts and seeds and discard, drizzle both halves with olive oil and season with salt and pepper. Place facedown on baking sheet and roast for approx. 35-45 minutes.
Allow squash to cool, peel off the skins or scoop out the insides and put into a food processor or blender contraption. Blend until smooth. Repeat with any remaining squash until all puréed.
Heat oil in a large skillet over medium heat. Add garlic and stir until fragrant about 2-3 minutes. Add 1 cup of butternut squash puree until begins to melt. Add 1 cup of half and half, 1/4 teaspoon of nutmeg, a pinch of paprika, and 1/4 teaspoon salt to the skillet. Add remaining butternut squash as desired. Stir all the ingredients to combine.
Meanwhile, bring a pot of salted water to a boil. Cook tortellini until just under the time on package instructions. Reserve some pasta water.
Add the spinach to the of the butternut mixture and turn to medium-low.
Add cooked and drained tortellini to the skillet with the butternut squash sauce and spinach and stir to combine. If the sauce is too thick, add more half and half or reserved pasta water.
