Make the syrup first. Combine the sugar, water, lemon juice and lemon peel (if using) in a medium saucepan. Bring to a boil over medium heat, stirring until the sugar dissolves, then simmer for 5 minutes. Remove from the heat and set aside to cool — the syrup should be cool when it meets the hot cake.

Heat the oven to 175°C (350°F). Grease a 9x13-inch (23x33 cm) baking dish, or line it with parchment paper, leaving an overhang on the long sides for lifting the cake out later.

Whisk the semolina, flour, sugar, baking powder and salt together in a large bowl until evenly mixed. Stir in the lemon zest.

Make the batter. In a second bowl, whisk the eggs, yogurt, oil and vanilla together until smooth and pale, about 1 minute. Pour the wet mixture into the dry ingredients and stir just until no dry streaks remain — do not overmix, or the cake turns tough. Scrape the batter into the prepared dish and smooth the top.

Bake at 175°C (350°F) for 30–35 minutes, until the top is deep golden and a skewer inserted in the center comes out clean. The cake should spring back lightly when pressed.

Pour the syrup. As soon as the cake comes out of the oven, pour the cooled syrup slowly and evenly over the hot cake — it will hiss and sink in. Pour in two or three rounds, letting each round soak in before adding more.

Cool and soak. Let the cake cool in the dish for at least 30 minutes so it drinks up the syrup. The cake is at its best once fully cool — the crumb turns moist and tender, never soggy. (Pictured: carrot revani, havuçlu revani, a popular variation with grated carrot folded into the batter.)

Slice into 12 squares and lift out with a spatula. Top each square with shredded coconut or crushed pistachios and serve at room temperature, with coffee or tea.