Step 1Heat the oven to 350 degrees. Grease a 13-by-9-inch baking pan. Line the bottom of the baking pan with aluminum foil, and lightly grease the foil. Set aside.
Step 2In the bowl of a food processor, combine the flour, sugar and salt. With the machine running, add the butter pieces and continue to process until the mixture resembles very fine, moist crumbs. The mixture won't come completely together in the processor.
Step 3Turn the crumbs out onto the prepared baking sheet and, using your hands, gently press to form a smooth, even layer. Bake until the crust is a light golden brown, 30 to 35 minutes.
Step 1While the crust is baking, combine the butter, brown sugar, maple and corn syrups in a saucepan. Heat over medium heat, stirring constantly, until the butter has melted and the mixture is completely combined and smooth. Cook one additional minute, then remove from heat and set aside.
Step 2In a large mixing bowl, whisk together the eggs, cream, vanilla and salt. Slowly whisk in about one-fourth cup of the warm sugar mixture to temper the eggs. Slowly whisk in another one-fourth cup, then slowly stir in the rest. When fully combined, stir in the pecans.
Step 3Pour the pecan mixture over the prepared crust. Return to the oven and bake until the pecan mixture is bubbling and jiggles when gently tapped, an additional 20 to 25 minutes.
Step 4Remove from the oven and place the sheet on a rack to cool completely. Lift the foil from the sheet to get the cookies out of the pan. Cut into squares and serve. The bars will keep nicely in an airtight container.