One of my all-time favorite desserts. I like Alison Roman's chilled carrot cake recipe, but I always use a half-batch of Claire Saffitz's brown butter cream cheese frosting. That frosting can't be beat. Here are my adjustments and notes for the recipe.
1) Combined zest from one lemon with the brown sugar and mixed it together before adding the other wet ingredients. The idea of the sugar molecules breaking down the zest might only work with granulated sugar, but I figured it wouldn’t hurt.
2) Used 1/2 cup whole wheat flour and 3/4 cup all purpose white flour.
3) Spice quantities: 1 tsp cinnamon, 1/2 tsp ground cardamom, 1/4 tsp (ish?) grated fresh nutmeg. This is just personal preference.
4) For the cream cheese frosting, if it's looking a little stiff, you can add a splash of lemon juice to loosen it up and add tang.
5) As written, a half batch of the cream cheese frosting calls for 227 grams of powdered sugar. I usually add less than this, initially starting with 150-60 grams, then add more as needed.
6) I've made the mistake of underbaking this cake, and it's very sad! I don't have much wisdom for preventing this. Sometimes the cake bakes in 40 minutes, other times it needs 45 minutes, maybe even more. But don't only go off the clean toothpick test - this has misled me in the past. The cake should be dark on top, and not jiggle in the center. Perhaps circle back to this point if you make this cake again and find more descriptors for when it's done.
7) When you chop up the dates, they stick together a lot and eventually morph into a mega-raisin thing. If you use your hands to mix them into the wet ingredients and shredded carrots, the liquid helps them separate and distribute.