Sponge cake cubes coated in apricot jam and nonpareils are a colorful Mexican bakery icon. This festive, family-friendly treat is a sweet, cheerful confection loved by all ages.
Preheat oven to 350°F (175°C). Line an 8x8-inch baking pan with parchment and lightly butter the surface to prevent sticking.
In a medium bowl, whisk together flour, baking powder, and salt to combine and aerate the dry ingredients.
In a stand mixer or with hand beaters on medium speed, cream butter and sugar together until pale and fluffy, about 3 minutes.
Add eggs one at a time, fully incorporating each before adding the next. Stir in vanilla extract.
With mixer on low, alternate adding flour mixture and milk in two additions, mixing gently until just combined. Do not overmix to maintain sponge texture.
Spread batter evenly in prepared pan. Bake for 22–26 minutes, until a toothpick comes out clean and top springs back. Cool in pan for 15 minutes, then transfer to a wire rack to cool completely.
Once the cake is fully cooled, cut into 1.5-inch squares. Warm apricot jam gently until fluid, then dip each cake square in the jam, ensuring all sides are coated.
Roll jam-coated squares in the nonpareil sprinkles, pressing lightly so the sprinkles adhere. Arrange on parchment and allow jam coating to set for at least 30 minutes before serving.