Step 1

Add the butter to a medium saucepan and place over medium heat.

Step 2

Occasionally stir to melt, then continue to stir as it goes from loud and bubbly to quiet and frothy.

Step 3

When it goes quiet, the browning process will happen pretty fast so don’t walk away from the pot. Keep stirring until the butter turns an amber color and gives off a nutty aroma.

Step 4

Remove from heat and pour the butter into a large mixing bowl. Make sure to scrape in all the brown bits at the bottom of the pot.

Step 5

Allow the butter to cool at room temperature and set the pot off to the side to cool as we’ll be using it for the frosting later.

Step 6

In the meantime, preheat the oven to 350F and grease a 10×15 jelly roll pan with non-stick spray.

Step 7

Once the butter has cooled, whisk in the sugar and brown sugar followed by the eggs and vanilla.

Step 8

Once smooth, whisk in the sour cream, baking soda, and salt.

Step 9

Off to the side – in a measuring glass, mix together the warm water and espresso.

Step 10

Now back to the mixing bowl – mix in half of the flour, then the warm espresso, then the rest of the flour.

Step 11

Pour the batter into the jelly roll pan and spread even. Bake for 25-30 minutes or until the center is soft and bouncy to the touch.

Step 12

Allow the cake to cool either at room temperature or in the refrigerator.

Step 13

While the cake cools, start on the frosting.

Step 14

Using the same pot we browned the butter in, wipe it clean and sprinkle in the dry milk powder.

Step 15

Place over medium-low heat and use a rubber spatula to stir occasionally at first. It won’t look like anything is happening for a few minutes, but slowly the powder will begin to clump as you stir.

Step 16

When you notice it’s starting to turn golden, constantly move it around to prevent any burning.

Step 17

As you stir, press into the clumps to help break them apart. Once the dry milk powder turns a graham cracker color, remove from heat and work on breaking down those clumps even further.

Step 18

Once you’ve reached a near-powder consistency, mix in the milk to form a paste.

Step 19

Scoop the paste into a small dish and chill in the refrigerator.

Step 20

By the time the cake has completely cooled, the toasted milk should also be cooled enough to continue making the frosting.

Step 21

In a large mixing bowl using a hand or stand mixer with the whisk attachment, mix together the toasted milk and room temperature butter.

Step 22

Then mix in the powdered sugar one cup at a time, followed by the vanilla.

Step 23

Spread the frosting over the cooled cake and top with chopped chocolate covered espresso beans.

Step 24

Now slice and enjoy!