In a large bowl, cream butter and erythritol until light and fluffy, 5-7 minutes. Beat in egg and vanilla. In another bowl, whisk almond flour, baking soda and salt; gradually beat into creamed mixture. Stir in chips. , Preheat oven to 325°. Drop dough by tablespoonfuls 2 in. apart onto ungreased baking sheets. Using a wet finger, press down on cookies to flatten. Bake until edges are lightly browned, 7-10 minutes. Cool completely on pans on wire racks.