The brittle may be made a few days in advance, but be sure to pick a day with low humidity.

Bring honey to a simmer in a saucepan over low heat. Cook, stirring constantly for 5 minutes. Add almonds and cook 5 more minutes, continuing to stir constantly. Then remove pan from the heat and stir another 2 minutes, being very careful as the honey is extremely hot. Pour the mixture onto the Silpat and, using the metal spatula, spread as thin as possible. Let the brittle cool, then break up into interesting shapes. Store in an airtight container in a cool location. Decorate cake top by inserting pieces of brittle and serve some on the side of each slice.