Old-fashioned English toffee, wonderful for sharing or gift-giving...if you don't eat it all!

English Toffee

1/2 cup plus 6 tablespoons butter
1 cup granulated sugar
2 tablespoons cold water
1/2 cup chopped pecans
1 teaspoon pure vanilla extract
Dash salt
1 (6-ounce) bag semisweet chocolate chips

1. Generously butter a cookie sheet.
2. Put butter, sugar, and water in a heavy saucepan over medium-high heat. Bring to a bubbling boil, stirring constantly with a wooden spoon, about 10 minutes. Continue cooking, without stirring, to a very brittle stage (300°F to 310°F | 150°C to 155°C on a candy thermometer). Or, when a small amount is dropped into cold water, the candy separates into hard, brittle threads.
3. Remove from heat and add nuts to mixture. Stir in vanilla and salt.
4. Pour onto prepared cookie sheet and spread to 1/4-inch thickness. Cool slightly, top with chocolate chips and spread once chocolate softens.
5. Cool completely and break into pieces. Store in an airtight container.

Makes 36 pieces.