Place pecan halves in a baking pan. Toast in a 350° oven, stirring occasionally, for about 8 minutes or until fragrant. When cooled, finely chop enough to make 1/4 c. (about 20 halves). Set chopped pecans and halves aside. Line 1 large or 2 small cookie sheets with parchment paper.
Cream butter and brown sugar well. Beat in egg yolk and vanilla. In a separate bowl whisk together flour, salt, cinnamon and espresso powder. Gradually add flour to butter mixture, mixing just until combined. Mix in the 1/4 c. chopped pecans and 1/2 c. chocolate chips.
Divide dough into 4 equal portions. On a lightly floured surface roll each into a 10 inch log. Place them at least 2 inches apart on the prepared cookie sheets. Lining the pecan halves up end to end, gently press them about 1/4 inch deep all along the length of the logs, no gaps between pecans. You should need 9-10 pecans for each log. Gently pinch the sides of the dough up and over the outer edges of the pecans. Most of the pecans should remain visible. Place cookie sheets in refrigerator to chill 45 minutes to an hour.
Preheat oven to 375°. Bake cookies 16-18 minutes or until edges are beginning to turn light brown. Place cookie sheets on wire racks to cool. Do not remove cookies at this time.
To make caramel, melt butter over low heat in heavy saucepan. Add cream, sugar and caramels. Stir continuously until caramels are melted, remove from heat and stir in vanilla. Let caramel cool a few minutes, stirring it occasionally, until it thickens slightly. (If caramel separates it will come together with stirring and cooling.) Spoon the warm caramel over the rows of pecans on each log.
Heat 1/2 c. chocolate chips in the microwave, stirring every 20-30 seconds until melted. Scrape the chocolate into a pastry bag or heavy duty sandwich bag. Cut a small hole in the corner and generously drizzle chocolate over the cookie logs. Lightly sprinkle with flaky sea salt if desired. Place cookie sheets in refrigerator until cookies are thoroughly chilled.
Place cooled cookies on cutting board. Cut into 1 inch slices along each log.