20 edible equilateral triangles.
Not many pictures of this process but will share what I have. Begin by making 3 batches of rice krispie treats.
The websites that helped the most are these: 20D Gingerbread (this has clear pictures of the pyramid shapes you will need) and Metallic D20 (this has an excellent description of how to make this out of cardboard). Oh yes, and20D template
Once you read those to posts, you can begin to see how this is going to come together.
Step 1. Make a cardboard mold. It will be three pieces: 2 pyramids and a middle section. And like the Metallic D20, the triangles need to be 4" on every side.
The two circle like shapes are the top and bottom, You cut these out of corrugated cardboard to make a 5 sided pyramid. Once you cut the outside shape and score the inside line, tape the open ends together and tah-dah: pyramid. Cover this in foil.
The long string of triangles makes the middle section. Once you cut the strip out of cardboard and score the inside lines, you need to wrap this all in foil before you attach the two ends together with packing tape or duct tape.
Step 2: Spray the foil with cooking spray so the RKT's don't stick! Fill the two pyramids with RKT. Then position one pyramid below the middle round section, lining up the sides. And fill that with RKT. Finally place the second pyramid on top and really press the whole thing together. Let this chill in the fridge to get firm.
Step 3: Cut out 20 triangles from modeling chocolate. Modeling chocolate allows you to blend the seams a little better. These need to be fairly thick. Use the yellow rings from the wilton rolling pin set.
Step 4: Place all 20 triangles of modeling chocolate on the rice krispie treat shape.
Step 5: Remove foil from cardboard and use the cardboard mold to help define your edges.
Step 6: Let the shape rest. I set one of the pyramids in a bowl, placed the shape in that. Here was the tricky part. As my 20D rested it started to sag. No worries. Just use the cardboard to reshape the whole thing. As the modeling chocolate dries a little, the shape will harden too.
This shows the shape sitting in a bowl. The foil would leave an impression on the modeling chocolate, so take that off. Then the chocolate should not stick to the cardboard. Nice flat edges to help shape it.
Step 7: Add numbers. I used a Wilton Number mold. But you could pipe these on with royal icing too. Once your numbers are on, spray the whole thing gold or silver!
To position this on the cake, I covered a small square with brown fondant, placed dowels in the bottom cake and set the 20D on that. I also ran kabob stick through the whole through to add stability.
Whew. It worked! A fabulous trophy cake for the game lover in your life.