- 3/4 cup granulated sugar
- 3/4 cup packed light brown sugar
- 1/2 cup heavy cream
- 2 tablespoons unsalted butter, cut into bits
- 1 1/4 cups pecan pieces, toasted
- Butter a 9-inch square metal baking pan.
- Sift granulated sugar through a sieve into a bowl to remove any lumps or large crystals, then rub brown sugar through sieve into bowl. Pour sugars into a 2 1/2- to 3-quart heavy saucepan, being careful not to get sugar on side of pan.
- Add cream, butter, and 1/4 teaspoon salt and cook over very low heat, stirring frequently with a wooden spoon and washing down any sugar crystals on side of pan with a pastry brush dipped in cold water, until sugar is dissolved (do not let simmer), 10 to 15 minutes.
- Clamp on candy thermometer, then boil syrup over moderately high heat, undisturbed, until it registers 236 degrees F and a teaspoon of syrup dropped into a small bowl of cold water holds a very soft ball when pressed between your fingers, 3 to 6 minutes.
- Remove pan from heat, leaving thermometer in place, and cool, undisturbed, until syrup registers 220 degrees F, 1 to 3 minutes. Stir syrup with cleaned and dried wooden spoon until thickened and creamy, 1 to 2 minutes, then immediately stir in pecans. Working very fast (syrup hardens quickly), pour into baking pan, scraping sides of saucepan with wooden spoon.
- Let mixture harden at room temperature, about 45 minutes. Cut and break into pieces.