Cream butter, sugar, vanilla, and salt till fluffy. Gradually stir in flour till blended. (Could take a few minutes.)
Once the dough begins to stick, form into a ball, then divide dough in thirds. On lightly floured surface roll each portion into 9” ropes.
Place inches apart on parchment line sheet. With finger or a teaspoon make a depression down the center of each rope. Fill depression with jam
Bake at 350° for 12-15 minutes or till golden. Cool on cookie sheet.
Blend powdered sugar and lemon juice and carefully drizzle over. Once the glaze has set, cut diagonally into 1“ cookies.