Preheat oven to 400*.  Trim the ends off the Brussels sprouts, wash and cut them in half, dry.  Place them on a baking sheet.

Melt butter, stir in olive oil — amounts don't have to be exact.  Pour over the Brussels sprouts and use your hands to make sure each piece has oil on it.

Add sea salt and pepper to your taste.

Bake about 30-45 min.  (Note:  To save work later, you might put them on parchment paper.)  Shake the pan occasionally or flip them for even browning.  Or do what we do:  as different pieces get golden brown, pull them out, eat all those dreamy pieces, and put it back in 'til the rest are done.  (I wonder how a splash of good balsamic vinegar would be on these…)