Pour the olive oil and fresh lime juice into a medium bowl.
Add the soy sauce and mix to combine.
Stir in the chilli powder, ground cumin, smoked paprika, garlic powder, onion powder, dried oregano, salt, black pepper and granulated sugar (optional).
Whisk until the spices are fully incorporated and the mixture is smooth.
Put the sliced chicken, beef or vegetables into a large resealable plastic bag or a shallow dish.
Pour over the marinade, seal or cover and chill in the fridge.
Marinate chicken or prawns for 30 minutes to 2 hours, or beef for 4 hours to overnight.
Remove from the fridge 15–20 minutes before cooking.
Cook in a hot frying pan over a high heat until browned and cooked through.