Preheat the oven to 180C/350F. Grease a large baking tray with one tablespoon of olive oil and set aside.
In a large mixing bowl, add your brussels sprouts, remaining olive oil, garlic salt, and pepper, and mix until combined.
Transfer onto the greased tray and bake for 25 minutes, or until golden and crispy on the outside.
Remove the brussels sprouts from the oven and serve immediately.
TO STORE: Leftover sprouts should be stored in the refrigerator, covered. They will keep well for up to 3 days. TO REHEAT: Either microwave for 30 seconds, pan fry until warm, or reheat in a preheated oven for 10 minutes.