Preheat the oven to 200°C/400°F. Lightly oil a 7 1/2 inch square deep cake pan and line the base with non‐stick baking paper.
Place the margarine and 3 tbsp of the honey in a saucepan and heat gently until melted. Reserve 1 tbsp lemon juice, then stir in the rest with the lemon rind and milk.
Sift together the flour, baking powder and nutmeg, then beat in with the semolina. Whisk the egg whites until they form soft peaks, then fold evenly into the mixture.
Spoon into the tin and sprinkle with sesame seeds. Bake for 25 ‐ 30 minutes, until golden brown. Mix the reserved honey and lemon juice and drizzle over the cake while warm.