Preheat oven to 375º F.
Remove any shaggy, brown leaves from the sprouts, slice in half (if they are large, slice into quarters) and place in a roasting pan. Toss with 2-3 Tbsp of olive oil, you just want them to have a thin coating, and a pinch or two each of salt and pepper. Roast, stirring after 10 minutes, until lightly browned and fork-tender, about 25 minutes.
While the sprouts roast, whisk all the vinaigrette ingredients except the olive oil together in a small bowl. Slowly add the olive oil while whisking to help emulsify.
When sprouts have finished roasting, throw them into a big bowl along with the matchstick apples, hazelnut pieces, and a few tbsp of the vinaigrette if eating right away. If not, wait until you’re ready to serve or just let guests spoon over the salad themselves. Top with crumbled Roquefort and some fresh ground pepper.