This uses a product called Hi Sweet, available from International Leisure Activities, Springfield, Ohio, 1-800-782-7448. (Catalog is $10, but if you decorate cakes, make candy, or love to bake, it's well worth it) The Hi-Sweet keeps the brittle from getting sticky.

2 cups sugar
1/2 cup warm water
3/4 cup Hi-Sweet
Cook to 300*
Add 2 cups roasted and salted peanuts
Cook until the color is right (med amber is what we like)
Add 1 Tbs butter and 1 tsp soda
Pour out onto parchment covered bun pan. If desired stretch when cool enough to handle.

Here's my variation using chip coconut

Deluxe Brittle
Substitute 6 oz fancy mixed nuts (no peanuts) and 2 oz chip coconut for the peanuts. I don't know why you couldn't use all coconut.