Preheat oven to 400°F. Line a baking sheet with foil and grease it with cooking spray.
Add the cubed butternut squash to the baking sheet then drizzle it with the olive oil and toss to combine. Sprinkle the squash with salt and pepper then roast it for about 15 minutes or just until it’s fork tender but still fairly firm.
Transfer the butternut squash to a food processor and process just until roughly pureed. (Do not over-process the squash or it will be too loose to hold its shape when in tot form.) Measure out 3 packed cups and transfer it to a large bowl.
Stir in the minced onions, breadcrumbs, egg, sage, and a pinch of salt and pepper.
Reduce the oven temperature to 350°F.
Using your hands, portion out 1- to 2-tablespoon portions of the mixture and shape it into tots. Arrange the tots on the lined baking sheet, spacing them 1/2-inch apart.
Bake the tots for 20 minutes then flip them once and bake them an additional 20 to 25 minutes or until crispy. Remove the tots from the oven and serve them with ketchup, mustard, ranch dressing or your preferred dipping sauce.