Preheat the oven to 400ºF.
Peel the potatoes, then dice them to ¼ inch pieces and put into a bowl.
Cut the Brussels Sprouts in ¼ inch pieces too and put them in the same bowl.
Add the olive oil and stir to combine.
Season with salt & pepper and mix well.
Transfer the potatoes and Brussels Sprouts to a baking pan in a single layer. Bake for 25 minutes in the oven until the potatoes soften up and start to turn brown.
Remove and serve.