Chop potatoes into chunks (no need to peel) and steam on the stovetop in a steaming basket until just tender (around 10 minutes). Or use a microwave steamer and steam on high for 8-10 minutes depending on microwave power.
Transfer potatoes to a roasting pan. Use the back of a spoon to lightly crush the potatoes (just enough to break the skin and flatten slightly). Combine garlic and olive oil and spoon over crushed potatoes. Bake potatoes for 20-30 minutes or until golden and crisp.
Meanwhile, place the dukkah on a plate. Add the salmon fillets and press firmly to coat on both sides.
Heat a non-stick frying pan over medium heat. Lightly spray with cooking oil. Add the salmon and cook for 2-3 minutes each side or until cooked to your liking. Transfer to a plate and cover with foil to keep warm.
Add the spinach to the pan and cook for 1 minute or until the spinach just wilts.