In a large bowl, mix together the fish paste with white pepper, sesame oil and cornflour. Spread a little bit of fish paste into each capsicum wedge.
Heat a large frying pan with 1 tablespoon oil over medium heat. Place the capsicum wedges down onto the pan and cook until brown, about 2-4 minutes. Turn over, cook for an additional 2-3 minutes. Transfer to a serving dish.
Heat the same pan with 1 tablespoon oil over high heat. Saute the garlic until aromatic, 2-3 minutes. Stir in the black bean sauce and sugar. Add cornflour slurry and heat until the sauce has thickened then pour over the capsicums.