Caramel-Nut Bars

• 2 1/4 sticks unsalted butter, room temperature, plus more for pan
• 1 1/2 cups (6 ounces) pecans
• 1 cup (4 1/2 ounces) salted cashews
• 1 cup (5 ounces) salted peanuts
• 3/4 cup packed light-brown sugar
• 2 1/4 cups all-purpose flour
• 2 1/2 teaspoons plus a pinch of salt
• 4 cups granulated sugar
• 1/2 teaspoon cream of tartar
• 1 cup heavy cream

1. Preheat the oven to 350F.
2. Butter a 15-by-10-inch rimmed baking sheet, and line with parchment paper, leaving a 1-inch overhang on long sides; set aside.
3. Spread nuts on another rimmed baking sheet.
4. Toast until nuts are fragrant and lightly golden around the edges, about 10 minutes.
5. Transfer nuts to a clean surface; spread evenly, and let cool completely.
6. Coarsely chop, and set aside.
7. In the bowl of an electric mixer fitted with the paddle attachment, beat 2 sticks of butter with the brown sugar on medium speed until light and fluffy, about 3 minutes, scraping down the sides of the bowl as needed.
8. With mixer on low speed, add flour and a pinch of salt; mix until just combined.
9. Transfer dough to prepared baking sheet, and cover with parchment paper.
10. Using a wine bottle or small rolling pin, roll along the length of pan to smooth dough.
11. (Alternatively, press the dough into the pan with the back of a large spoon.)
12. Bake until lightly golden, 10 to 12 minutes.
13. Transfer to a wire rack to cool completely.
14. Combine granulated sugar, cream of tartar, remaining 2 1/2 teaspoons salt, and 1 cup water in a wide, heavy-bottom saucepan.
15. Cook over high heat, without stirring, until some sugar begins to melt and turn golden, 5 to 7 minutes.
16. Reduce heat to medium; continue to cook, stirring occasionally with a wooden spoon, until sugar is completely melted, mixture is deep golden, and a candy thermometer registers 300F (hard-crack stage).
17. Stirring constantly, carefully pour cream slowly down the side of the pan (it will spatter) until fully combined.
18. Remove from heat; add remaining 1/4 stick butter and stir to combine.
19. Transfer caramel to a heatproof bowl to cool for 10 minutes.
20. Stir in nuts; spread caramel mixture over cooled crust.
21. Bake until caramel is set, about 10 minutes.
22. Transfer to a wire rack to cool.
23. Cut into 3-by-2-inch bars.
24. Bars can be kept in an airtight container at room temperature for up to 1 week.
25. Follow instructions for Caramel-Nut Bars, reducing salt in the caramel to 1 teaspoon and adding 8 ounces melted semisweet chocolate and 2 tablespoons Dutch-process cocoa powder to the caramel along with the 1/4 stick butter.
26. Proceed with the recipe.
27. A combination of salted nuts is stirred into a bowl of freshly cooked caramel.
28. The caramel-nut mixture is spread atop a cooled cookie base before the bars are baked a second time to set.

butter, pecans, cashews, peanuts, lightbrown sugar, flour, salt, granulated sugar, cream of tartar, heavy cream

Taken from www.epicurious.com/recipes/food/views/caramel-nut-bars-390357 (may not work)