Step 1

Pre-heat your toaster oven or air fryer on "bake" setting to 350°F (175°C)

Step 2

In a small pan, heat light brown sugar and water. Bring to a gentle simmer and swirl the pan occasionally. Once the sugar has caramelized and reached your desired color, immediately turn off heat.

Step 3

Pour caramel into ramekin. Allow to cool and set.

Step 4

In a bowl, break egg yolks and stir in one direction using a spatula.

Step 5

Gradually add condensed milk, evaporated milk, key lime juice, and vanilla. Continue stirring in one direction until all the ingredients are well-blended. Do not over stir.

Step 6

Place a fine mesh strainer over a glass measuring cup and pour the egg mixture.

Step 7

Pour egg mixture over the prepared ramekin.

Step 8

Place a pan on the oven tray. Gently transfer ramekin in the pan. Carefully pour hot water into the pan (bain marie, also known as water bath), not the ramekin. Cover with foil.

Step 9

Slowly insert the tray into the middle of the oven.

Step 10

Bake for 35 minutes or until the middle part comes out clean when a toothpick or knife is inserted.

Step 11

Allow the Leche Flan and ramekin to completely cool. Refrigerate to chill.