Brussels Sprouts and Walnuts

1 cup walnuts , coarsely chopped 1 lb Brussels sprout , trimmed and halved 1 pint small shallots or 1 pint white pearl onion 2 tablespoons unsalted butter ,[...]

2 (10 ounce) packages Brussels sprouts 2 ounces thick slab bacon , cut into 3/4 inch cubes 3 -4 shallots , sliced thin lengthwise 1/2 cup walnut pieces 1/2[...]