Agate Cake

INGREDIENTS

Assorted hard candies (about 1-2 oz per large agate slice)

Non-stick heavy-duty foil

Silver edible luster dust (optional)

Vodka (optional, if you’re using the silver luster dust)

6 oz

butter (at room temperature)

4 3/4 oz

granulated sugar ((2/3 cup))

5 oz

brown sugar ((2/3 cup packed))

eggs (at room temperature)

2 tsp

vanilla extract

8 fluid_ounces

buttermilk ((1 cup) at room temperature)

4 oz

sour cream ((1/2 cup) at room temperature)

2 tbsp

water or coffee

7 4/5 oz

all-purpose flour ((1¾ cups))

3 oz

unsweetened cocoa powder ((1 cup))

1 1/2 tsp

baking soda

1/2 tsp

salt

6 fluid_ounces

pasteurized liquid egg whites ((3/4 cup))

24 oz

powdered sugar ((6 cups))

1/2 tsp

salt

24 oz

unsalted butter (at room temperature (6 sticks))

2 tbsp

vanilla extract

Gel food coloring (I used Americolor Electric Purple, Violet, Sky Blue, Navy Blue, Electric Pink, and Super Red)