Lier's food scene is unpretentious and good. The town is famous for its "Lierse vlaaikes" — small, round pastries filled with a spiced biscuit-and-butter filling that are unique to the region and have been protected as a local product. You will find them in most bakeries in town; they make an excellent breakfast or mid-morning snack with coffee.
For proper meals, the area around the Grote Markt and along Aarschotsesteenweg has a range of Belgian restaurants and brasseries. Expect the usual Flemish staples — mussels, stoofvlees (beef stew in dark beer), carbonnade Flamande, and generous portions — alongside the occasional Italian or French kitchen. Prices are noticeably lower than in Antwerp for equivalent food.