Wash the sprouts and cut in half.
Drizzle the sprouts with 1 1/2 teaspoons of olive oil and season with salt and pepper.
Roast in the oven at 220C for about 20-25 minutes, making sure to stir/rotate the sprouts at least once.
Meanwhile, when that's almost done cooking, heat another 1 1/2 teaspoons of olive oil over medium low heat.
Peel and chop the 3 garlic cloves, saute until they just begin to turn brown, then remove from heat and stir in the fresh juice of one lemon.
Pour that mixture over the brussels sprouts, stir and you're done.