measurements are not exact and don't need to be... follow your intuition and taste buds on this one!
Coat the bottom of a nice big pan with olive oil, lightly saute the garlic for a minute or so. Place the brussel sprouts cut side down in the olive oil and roast the brussel sprouts slowly over medium low eat until they start to become dark and caramely. Flip and cook on the other side until the brussel sprouts begin to soften and are cooked through, season with salt and pepper to taste.
Meanwhile place the pecans in another pan and slowly toast over low heat until the nuts become fragrant and toasty brown colored, stirring often.
Finally, I highly recommend topping with a generous drizzle of sweet balsamic vinegar and some parmesan cheese or nutritional yeast. This is seriously tasty!