Preheat your oven to 160°C (325°F). Arrange 4–6 small ramekins in a deep roasting pan so they sit comfortably without touching.
Make the caramel: in a small saucepan combine Granulated Sugar with about 2 tablespoons of Water and a splash of Lemon Juice to help prevent crystallization. Heat over medium without stirring (you can gently swirl the pan) until the syrup turns a deep amber color, then immediately pour and swirl it into the bottoms of the ramekins to coat evenly; set aside to harden.
Warm the milks: in a separate saucepan gently heat Sweetened Condensed Milk and Whole Milk just until warm (do not boil), stirring to combine.
Prepare the eggs: in a mixing bowl lightly whisk Eggs with a pinch of Salt until blended. Slowly temper the eggs by pouring the warm milk mixture into the eggs in a thin stream while whisking constantly to avoid scrambling.
Stir in the flavoring: add Vanilla Extract to the custard and mix briefly. For an extra-smooth texture, pass the custard through a fine-mesh sieve into a pouring jug.
Pour the strained custard gently over the set caramel in each ramekin, leaving a little headspace. Cover each ramekin loosely with foil.
Prepare a water bath by pouring hot water into the roasting pan around the ramekins until it reaches about halfway up their sides. Carefully transfer the pan to the oven and bake for 40–50 minutes, or until the custard is just set but still slightly wobbly in the center. (Alternatively, you can steam the covered ramekins over simmering water for about 15–20 minutes.)
Remove the ramekins from the water bath and let them cool to room temperature. Then refrigerate for at least 4 hours or overnight to fully set and chill.
To serve, run a thin knife around the edges to loosen, invert each ramekin onto a plate, and lift—allowing the caramel to drizzle over the custard. Serve chilled.
