Place the two cod fillets on a baking tray. Mix the breadcrumbs with the garam masala, lemon zest and a generous grind of black pepper. Top the cod evenly with the breadcrumb mixture and bake for 10 minutes, until the fish is cooked through and the topping is crispy.
Meanwhile, slice the cucumber thinly with a mandolin if possible or as thin as possible with a knife or vegetable peeler. Mix with the salt and set aside for 5 minutes.
After 5 minutes, rinse the cucumber well in cold water. Place it in a bowl with the dill, white wine vinegar, chilli flakes and garlic. Toss together and serve immediately with the cod and lemon wedges for squeezing over.
To get one of your recommended servings of oily fish a week, swap the cod for an oily fish, such as salmon.