Preheat oven to 150°C (not fan-forced).
Make the caramel: Add the 250g sugar to a pot over medium heat. If your pot is small, add the sugar in batches so it melts evenly. Do not stir, instead, swirl the pot occasionally to help it melt and colour evenly. Once the sugar has melted and turned a dark copper colour, carefully add 2 tbsp water and swirl to combine. Quickly pour the caramel into your baking tin, tilting to coat the base evenly.
Infuse the milk: In a saucepan, heat the 550ml milk with the vanilla beans, empty pod, and 2 slices orange peel until it begins to simmer. Remove from heat and let it steep for 10 minutes.
Make the custard: In a separate bowl, slowly whisk together the 3 eggs, 2 egg yolks, and 80g sugar until smooth. Strain the milk mixture through a fine sieve into a jug, discarding the pod and peel. Slowly pour the warm milk into the egg mixture while whisking gently to temper the eggs. Once combined, strain the mixture again to remove any cooked egg bits.
Prepare the water bath: Place the caramel-lined tin inside a larger, deep baking tray. Pour the custard into the tin, straining one final time as you do. Pour room-temperature water into the outer tray so it comes halfway up the sides of the tin.
Bake: Bake for about 1 hour, or until the custard is set but still has a slight wobble in the centre. Cooking time may vary depending on your tin size. (We used a 20cm round cake tin.)
Cool and unmould: Remove from the oven, let cool to room temperature, then refrigerate overnight. To serve, run a thin (non-serrated) knife around the edge, place a plate on top, and flip upside down. Tap gently until the crème caramel releases.
