To make butternut squash purée, coat 1 peeled, seeded, and quartered butternut squash with 1 tablespoon (14 grams) olive oil. Place on a baking sheet lined with parchment paper. Roast in a 400°F (200°C) oven until soft, 45 minutes to 1 hour. Let cool completely. Scrape out pulp. Transfer pulp to the work bowl of a food processor; process on high until puréed. Refrigerate for up to 5 days.