Preheat your oven and line your baking pan. You want easy cake removal, since the milky soak makes serving a breeze (and cleanup so much simpler!).
Whisk together the oil and sugar until it looks pale and glossy. Drop in the egg yolks, milk, and orange zest, whisking until smooth and fragrant with citrus.
Sift your dry ingredients: flour, all the warming spices, baking powder, and salt. Fold them gently into the wet mix, stopping as soon as it comes together—no overmixing or you’ll lose that fluffy, moist crumb.
In a separate bowl, beat egg whites until soft peaks form. Gently fold them into the batter, using big, sweeping strokes. This keeps your cake light and tender with just the right bounce.
Stir in grated carrots, raisins, and walnuts. Spread the batter into your prepared pan and smooth out the top.
Bake until the cake is just set, golden brown, and springs back lightly to the touch. Let it cool completely before the best part—the soak!
Mix together evaporated milk, sweetened condensed milk, heavy cream, and a splash of vanilla. Poke holes into the cooled cake (a skewer or chopstick works great), then slowly pour the milk mixture over the entire surface. Let the cake chill and soak up every drop in the fridge. This takes a little time, but it’s completely worth it for that tres leches magic.
Beat softened cream cheese with vanilla, a pinch of salt, and heavy cream until totally smooth. Gradually add icing sugar to form a fluffy, spreadable topping.
Frost the chilled, soaked cake. Tidy up the edges, then sprinkle extra walnuts and cinnamon for that signature carrot cake finish. Slice and serve when you’re ready for something extra-special.