Peel the carrots and cut them into long chunks about 2,5" and then cut those in half.
Chop up the garlic, and place the garlic and the carrots into a large baking dish.
Sprinkle salt and pepper over the carrots and give them a drizzle of olive oil.
Pour the Guinness and the balsamic vinegar over the carrots.
Bake the carrots in a preheated oven at 400°F (200°C) for 45 minutes.
Then turn off the heat in the end, stir the carrots but leave the dish in the hot oven for another 30 minutes.
Remove the dish from the oven and stir the carrots.