Sericaia – Portuguese milk and egg dessert with cinnamon

Prepare a round ceramic baking dish about 28 cm in diameter and at least 5 cm deep. Thinly butter the base and sides with all the measured butter. Separate all the yolks from the whites: put the yolks in a large bowl and the whites in a clean, dry bowl without any traces of grease. Keep both parts of all six eggs. Cut a few strips of peel from a washed and scrubbed lemon, without the thick white pith, and weigh out the required 5 g.

Pour all 500 g of weighed milk into a saucepan. Add all the lemon peel strips, the piece of cinnamon stick and all the salt. Slowly bring almost to the boil, then heat gently for about 3–5 minutes, taking care that the milk does not boil over. Use a spoon to remove every strip of peel and the cinnamon stick; they will not be needed again. Keep all the infused milk.

Add all the sugar to the yolks and whisk until combined. Add all the flour and mix again. Gradually pour in some of the hot milk, whisking vigorously until smooth and fluid. Pour this mixture into the saucepan with the remaining milk. Heat over a low or medium heat, whisking constantly and reaching the base and sides of the pan. Once it has thickened noticeably and the first slow bubbles appear, lower the heat and cook for about another 2 minutes, still stirring. The custard should be smooth and resemble a thick pudding.

Transfer all the custard to a wide bowl, scraping the saucepan thoroughly with a spatula. Leave for about 30 minutes, stirring occasionally, until lukewarm, not hot. This means the egg whites do not collapse suddenly when combined with it. Towards the end of cooling, preheat the oven to 200°C with conventional top and bottom heat. Keep the buttered dish out of the oven; do not heat it while empty.

Beat all the reserved egg whites with an electric mixer, starting at a lower speed. Once foamy, increase the speed and beat until thick and glossy, with peaks that hold their shape. Stop before the whites become dry and lumpy. Do not add any sugar: all the measured sugar is already in the custard.

Add about a quarter of the whipped whites to the lukewarm custard and gently stir to loosen it. Add the remaining whites in two batches, lifting the mixture with a spatula from the bottom upwards and turning the bowl each time. Combine all the whites with all the custard, stopping once the larger white streaks disappear. Do not use the mixer again, to keep the mixture airy.

Spoon all the mixture into the buttered dish in large dollops. Alternate the direction of each spoonful, one lengthways and the next crossways, leaving a gently uneven surface and space below the rim for rising. Scrape all the mixture from the bowl with a spatula. Sift all the measured ground cinnamon through a small sieve to cover the surface in an even layer.

Place the dish on the middle shelf of the preheated oven. Bake for about 30–35 minutes at 200°C. The dessert should rise, the cinnamon top should dry and crack naturally, and the center should be set, without any liquid mixture. If the center still moves distinctly like a liquid, bake for a few more minutes. Do not cut into the hot surface and do not touch it. The sericaia will settle slightly after it comes out of the oven; this is normal.

Set the dish on a trivet for about an hour, until it is no longer hot. Then cover and refrigerate for at least 2 hours. Serve the sericaia well chilled, spooning it out with a large spoon or dividing it into eight portions directly in the dish. Each portion should include the delicate center and cinnamon top. Keep any leftover dessert covered in the refrigerator.