Step 1

Preheat the oven to 325 degrees F and lightly mist 14 4-ounce mason jars* with non-stick spray.

Step 2

Place the flour, brown sugar, baking powder, baking soda, and salt in a large mixing bowl and whisk to combine.

Step 3

Beat in the soft butter on medium-low speed, for about 1 minute or until the mixture resembles damp sand.

Step 4

Beat in the egg on medium-low speed, until completely incorporated (about 1 minute).

Step 5

Scrape the bottom and sides of the bowl with a silicone spatula, and add the sour cream, milk, and vanilla.

Step 6

Beat on medium-high speed for one minute, to aerate the batter and build the cake's structure.

Step 7

Transfer the batter to the prepared jars, and bake for 25 minutes, or until a toothpick inserted in the thickest part comes out clean.

Step 8

Cool completely, then pour the tres leches mixture over the cakes, chill for 2 hours, and top with whipped cream, dulce de leche, and toasted coconut.

Step 9

Whisk the condensed milk, evaporated milk, and half & half together in a large measuring cup.