My mom has been making these roasted winter veggies for basically as long as I can remember. I believe she got the recipe from Southern Living, although I can't seem to find it online now.
The basics are brussel sprouts, whole baby carrots and pearl onions, roasted in the oven with some garlic, olive oil, rosemary and sage. I use all frozen vegetables, which I'm sure a lot of fancie foodies would sneer at, but it's the most convenient and frozen veggies are surprisingly good and just as nutritious. I usually just wing it when making these because I don't have the recipe written down, and it's all pretty hard to mess up. You put the frozen veggies (a bag of brussel sprouts, a bag of carrots, and a small bag of pearl onions) on a baking sheet, still frozen. Then coat them with a couple swirls of olive oil (probably 2 tablespoons) and sprinkle fresh chopped garlic, rosemary and sage. (I use dried rosemary and sage, but fresh garlic makes the difference here, so don't skimp.) Heat the oven to a high temperature - around 425, and cook for around 45 minutes to an hour. They'll take a long time to get roasted since they're frozen, although it may take a little less than an hour for some ovens. Just keep an eye on them! But, I like for them to get a little charred so leaving them in too long isn't often a problem.
If you're scared to "wing it" and want to follow a recipe, you can use this one I found at The Daily Green using fresh veggies. This one leaves out the herbs, so you'll have to add those for the extra flavor, but it's a good representation of the concept.
I make these vegetables all the time, and there is so much flavor in them that sometimes I just make a big bowl of them for dinner and I swear I'm eating garlic mashed potatoes. Ok, not really, but they're really tasty!