In a large mixing bowl, beat butter at medium speed with a mixer until smooth and creamy. Add ¼ cup confectioners’ sugar and vanilla extract, beating until light and creamy. Add flour and salt, stirring until well combined. Add walnuts and thyme, stirring well.
Using a levered 2-teaspoon scoop, drop dough 1 inch apart onto prepared baking sheets.
Bake until edges of tea cakes are light brown, approximately 14 minutes. Transfer to wire cooling racks, and sprinkle with remaining ¼ cup confectioners’ sugar. Let cool completely.
Store in an airtight container with waxed paper between layers.
Just before serving, garnish with a dusting of additional confectioners’ sugar. Garnish each tea cake with a fresh thyme sprig, if desired.
Recipe by TeaTime Magazine at https://teatimemagazine.com/walnut-thyme-tea-cakes-recipe/