Brussel Sprouts from a Medieval Forest

On a whim, I tried combining a few Northern European late autumn-ripening foods. These tastes are meant to be eaten together. The red apple peel is especially pretty against the bright green of the lightly sauteed sprouts.
Clean and cut in half:

• 1 - 2 stalks of brussel sprouts

Heat in a pan:

• 1 - 2 Tablespoons goose fat (or butter)

Saute brussel sprouts with:

• 1 onion, thinly sliced
• 1 - 2 apples, unpeeled but chopped small
• ¼ - ½ cup fresh walnuts, shelled and quartered
• Salt and pepper to taste

When sprouts turn bright green and onions soften, remove from heat and sprinkle with

• 1 - 2 Tablespoons walnut oil
• 1 - 2 Tablespoons apple cider vinegar

Adjust salt and pepper before serving.