Tin Roof Semifreddos with Roasted Pears and Spanish Peanuts

When I get an idea for a dessert, the image is right there in my head, so close I can imagine its flavor, begin to feel its subtle textures, and envision what final form it will take. It’s as though I’m in a sweet think tank, surrounded by chocolate, caramel, nuts, and other sweet ingredients. That’s the easy part. But I usually have to make a dessert at least four times before I can get it to work. Each variation comes closer and closer to the final version. These experiments are generally