1. Infuse the Milk: In a saucepan, combine the whole milk, granulated sugar, cinnamon stick, lemon peel, and orange peel. Heat the mixture over medium heat, stirring occasionally, until it’s warm and fragrant, but not boiling. Remove the pan from the heat and let the flavors infuse for 10 minutes. Discard the cinnamon and citrus peels.

2. Thicken the Mixture: In a separate bowl, whisk together the cornstarch and 1/2 cup of all-purpose flour. Gradually add a cup of the warm milk mixture to the cornstarch-flour blend, whisking constantly to create a smooth slurry. Return the slurry to the saucepan with the remaining milk and cook over medium heat, stirring continuously, until the mixture thickens into a pudding-like consistency.

3. Chill and Cut: Pour the thickened milk mixture into a greased baking dish or pan, smooth the top, and let it cool completely. Once chilled, the mixture will firm up, allowing you to cut it into squares or rectangles.

4. Coat and Fry: Prepare the coating by beating the eggs in one bowl, placing the additional 1 cup of flour in another bowl, and mixing the white sugar and ground cinnamon in a third bowl. Dredge each piece of the chilled milk mixture in the flour, then dip it in the beaten eggs, and finally roll it in the cinnamon-sugar mixture.

5. Heat the sunflower oil in a frying pan over medium heat. Fry the coated pieces until they’re golden brown on all sides. Drain the fried Leche Frita on paper towels to remove any excess oil.

6. Serve and Enjoy: Leche Frita is best served warm or at room temperature.