Prep Brussels sprouts by removing damaged leaves, slicing the bottoms and cutting in half vertically. Transfer to a bowl and toss with 1 tbsp of olive oil and season with salt and pepper to taste. Transfer to a rim lined baking sheet, placing the sprouts cut side down.
Cut butternut squash into cubes (or buy store-bought already cut saves a ton of time!) transfer to a bowl and toss with remaining 1 tbsp of olive oil, and season to taste with salt and pepper.
Place both trays in the oven, sprouts on top rack so the char a bit, and squash on bottom rack. Roast for 15 minutes. Remove from oven and allow to cool.