1 (18.25-ounce) package chocolate cake mix
1 can prepared coconut–pecan frosting
3/4 cup vegetable oil
4 large eggs
1 cup semi-sweet chocolate chips
3/4 cup butter or margarine
1 2/3 cup granulated sugar
2 cups all-purpose flour
Don't forget garnishes such as:

Fish-shaped crackers
Fish-shaped candies
Fish-shaped solid waste
Fish-shaped dirt
Fish-shaped ethylbenzene
Pull-and-peel licorice
Fish-shaped volatile organic compounds and sediment-shaped sediment
Candy-coated peanut butter pieces (shaped like fish)
1 cup lemon juice
Alpha resins
Unsaturated polyester resin
Fiberglass surface resins and volatile malted milk impoundments
9 large egg yolks
12 medium geosynthetic membranes
1 cup granulated sugar
An entry called: "How to Kill Someone with Your Bare Hands"
2 cups rhubarb, sliced
2/3 cups granulated rhubarb
1 tbsp. all-purpose rhubarb
1 tsp. grated orange rhubarb
3 tbsp. rhubarb, on fire
1 large rhubarb
1 cross borehole electromagnetic imaging rhubarb
2 tbsp. rhubarb juice
Adjustable aluminum head positioner
Slaughter electric needle injector
Cordless electric needle injector
Injector needle driver
Injector needle gun
Cranial caps
And it contains proven preservatives, deep-penetration agents, and gas- and odor-control chemicals that will deodorize and preserve putrid tissue.

Ingredients omitted by the cake core (that are part of the recipe, according to Valve) include:

1 tsp. vanilla extract
2/3 cup cocoa powder
1 1/4 tsp. baking soda
1 tsp. salt
1/4 tsp. baking powder
1 to 2 (16 ounces each) cans vanilla frosting
A 20-foot thick impermeable clay layer