Step 1

Toast the Sugar: Adjust oven rack to middle position, preheat to 350°F (180°C), and place the sugar in a 10-inch stainless steel skillet. Toast in the oven until fragrant and pale gold, like white sand, stirring thoroughly every 20 minutes or so to circulate sugar away from the edges of the pan. The whole process will take about 1 hour, but it can vary significantly depending on oven temperature accuracy, skillet size and shape, and frequency of stirring. Pour warm sugar into a 2-quart glass baking dish (or similar) to speed cooling and let it cool to approximately 70°F (21°C) before use. The cooled sugar can be used right away, or it can be stored in an airtight container indefinitely.

Step 2

Brown the Butter: In 3-quart stainless steel saucier, melt butter over medium-low heat until fluid. Increase to medium and simmer, stirring with a heat-resistant spatula while butter hisses and pops; adjust heat as needed, so that dairy solids will not scorch before all the water can boil away. Continue cooking and stirring, scraping up any brown bits that form along the pan, until butter is golden yellow and perfectly silent (an indication the water has entirely boiled away). The entire process should take about 15 minutes; substantially shorter or longer times may indicate improper heat settings.

Step 3

Pour into bowl of a stand mixer (there will be about 9 3/4 ounces or 276g), along with all the toasty brown bits, and cool until thick, creamy, and opaque, or approximately 70°F (21°C). This can be done passively over the course of several hours, or in about 20 minutes with a cold-water bath using a few ice cubes. Alternatively, the brown butter can be refrigerated up to a week in an airtight container and then warmed to about 70°F (21°C) before use.

Step 4

Getting Ready: Adjust oven rack to lower-middle position and preheat to 350°F (180°C). Lightly grease three 8-inch anodized aluminum cake pans and line with parchment (explanation and tutorial here). If you don’t have three pans, it’s okay to bake the cakes in stages; the batter can be held at room temperature during this time.

Step 5

For the Cake: In the bowl of a stand mixer fitted with a paddle attachment, combined the cooled brown butter, the cooled toasted sugar, baking powder, vanilla, water, salt, and baking soda. Mix on low speed to roughly incorporate; then increase to medium and beat until soft, fluffy, and pale, about 8 minutes. About halfway through, pause to scrape the bowl and beater with a flexible spatula.

Step 6

With the mixer still running, add eggs one at a time, letting each fully incorporate before adding the next. Reduce speed to low and sprinkle in about 1/3 of the cake flour, then drizzle in 1/3 of the milk. Repeat with remaining flour and milk, working in thirds as before.

Step 7

When the batter looks smooth, scrape the bowl and beater with a flexible spatula; then fold the batter once or twice from the bottom up to be sure everything is well-combined. The batter should look creamy and thick but not stiff.

Step 8

Divide evenly between prepared cake pans (about 27 ounces or 765g). Stagger pans together on one oven rack and bake until puffed, firm, and pale gold, about 35 minutes. If oven has uneven heat, pause to rotate the pans after about 16 minutes. Alternatively, bake two layers at once and finish the third later.

Step 9

Cool cakes directly in their pans until no trace of warmth remains and then run a butter knife around the edges to loosen. Invert onto a wire rack, peel off the parchment, and return cakes right side up (covered in plastic, the cakes can be left at room temperature for a few hours). Prepare buttercream.

Step 10

For the Crumb Coat: Level cakes with a serrated knife (full directions here) and set scraps aside for snacking. Place one layer on a heavy cast iron turntable. If you like, a waxed cardboard cake round can first be placed underneath, secured to the turntable with a scrap of damp paper towel. Top with exactly 1 cup buttercream, using an offset spatula to spread it evenly from edge to edge. Repeat with second and third layers and then cover the sides of the cake with another cup of buttercream, spreading it as smoothly as you can (tutorial here). Refrigerate cake until buttercream hardens, about 30 minutes.

Step 11

To Finish: Rewhip remaining buttercream to restore its creamy consistency and then use to finish and decorate the chilled cake as desired. Let the cake sit out until it reaches an internal temperature no cooler than 70°F (21°C) before serving, otherwise it will be too cold and seem greasy and dense. Cut with a chef’s knife to serve and cover exposed edges with leftover buttercream to keep the cake moist. Under a cake dome, the frosted cake will keep for 3 days at room temperature.