Mix the ingredients of the marinade together in a glass bowl. This includes the orange juice, Dijon mustard, ground paprika, maple syrup, ketchup, olive oil, salt and pepper to taste and the crushed garlic clove. Stir until well combined.
Cut your chicken fillets into cubes about 1 inch wide. Pop them into the bowl with the marinade and stir until well-coated in the sauce.
If you have time, cover the bowl with clingfilm and leave it in the fridge for 20 minutes or overnight.
When you’re ready to grill or BBQ, take the bowl out of the fridge and thread the pieces of chicken onto a skewer, about 5-7 pieces per skewer. If you’re using wooden skewers it’s a good idea to soak them in cold water for 20 minutes before you start.
If you’re cooking on the BBQ, brush the grills with oil. If you’re cooking on a grill pan then heat 1-2 tablespoons olive oil over a medium flame.
Cook the chicken kebabs for about 5-7 minutes on each side. Check that the large pieces on either end are cooked well, and that all pieces are cooked through.
Serve with some grilled pitta bread and a refreshing summer salad.