Salted Pretzel Church Window Cookies

Coarsely chop 1 1/2 cups nuts. Finely chop remaining 3/4 cup nuts.

Melt butter in a double boiler or a heat-safe bowl set over simmering water, stirring occasionally. Add semisweet and dark chocolate chips. Heat, stirring constantly, until melted. Remove from heat; let cool 10 minutes, stirring occasionally. Meanwhile, put 2 (15x18-inch) pieces of parchment paper on a work surface.

Add marshmallows and coarsely chopped nuts to chocolate mixture; stir gently to coat. Spoon half of chocolate mixture onto center of each piece of parchment paper. Using the parchment or a silicone spatula, shape each portion into a 12-inch-long log. Wrap logs tightly in parchment; chill until surface of chocolate is slightly firm and pulls away from parchment (center will still be soft), 15 to 20 minutes.

Meanwhile, combine finely chopped nuts and pretzels in a small bowl. Put 2 more 15x18-inch pieces of parchment paper on work surface. Sprinkle each with half of pretzel mixture. 

Carefully transfer chilled logs (they will still be soft) to the parchment with pretzel mixture; roll, gently pressing to coat all sides. Wrap logs tightly in parchment paper; chill until firm, at least 4 hours or up to overnight.

Cut each log into 1/2-inch-thick slices, trimming off uneven ends as needed. (To store, layer between sheets of waxed paper in an airtight container and chill up to 3 weeks.)