Place the salmon fillets under a medium grill for 12-15 minutes, until cooked.
Whilst the salmon is cooking place the spinach leaves in a large frying pan and gently heat the pan, stirring the spinach allowing it to wilt, but not burn.
Whilst the salmon is cooking, and spinach wilting mix the mayonnaise, lemon juice and chopped capers in a small serving dish.
Divide the wilted spinach between two plates, top with the salmon and spoon the mayonnaise mixture over and serve with the lemon wedges.