Make pecan crust: Pre-heat oven to 300 degrees F and line an 8-inch square baking pan with parchment paper. In a food processor, pulse pecans, softened butter, Swerve sweetener, and salt until well combined. Press pecan mixture onto bottom of pan until evenly spread. Bake until crust is lightly toasted, about 10 minutes or more. Remove from oven and let crust cool to room temperature.
Make peanut butter layer: In a pot, heat butter (4 tablespoons) and peanut butter and stir until until melted. Turn off heat and add Swerve sweetener, almond flour and vanilla. Stir until thoroughly combined. Spread mixture evenly across pecan crust.
Add chocolate layer and finish: In a small microwaveable bowl, microwave chocolate chips and ½ tablespoon butter in 30-second increments. After each 30-second increment, take out and stir. Stop this process as soon as chocolate chips stir to a smooth consistency. Spread melted chocolate over the peanut butter layer. Sprinkle with flaky sea salt if you like. Refrigerate for one hour to set. Store in refrigerator after cutting.
Notes
Store covered in refrigerator when not eating. Bars stay well in the fridge for 2 to 3 weeks and can even be frozen.