Add butter, ground almonds, sugar, lemon juice and rind to flour,
Knead with hands until dough is very smooth and firm.
Chill for at least 2 hours or overnight.
Roll small parts of dough between waxed paper to 1/8″ to 1/4″ thickness; dough is easier to roll if it is left out of refrigerator for at least 15 minutes. See notes ***
Cut into 1″ or 2″ rounds.
Bake cookies on greased and floured cookie sheets, or on parchment paper covered sheets, in moderate oven (350 F) 10 minutes, or until golden. Remove cookies carefully. Very thin cookies are fragile.
After cooling, put two cookies together with jam in between, sandwich fashion.
Melt chocolate and 1 tablespoon butter over hot, not boiling, water. Beat until smooth. If necessary, add more butter or up to 1 tablespoon hot water to achieve spreading consistency.
Frost cookies on top. Decorate tops with slivered almonds immediately, while frosting is still soft. Cool thoroughly before storing. Will freeze up to 1 month.
Roll dough between waxed paper. Dough is very short. It is best to loosen the rolled dough from both pieces of waxed paper. To do this, carefully lift the waxed paper from the top of the dough. Then add the top back on and carefully flip the dough over, so that the bottom is now the top. Now just pull the waxed paper off of the top. Now cut out shapes, pick them up with a cookie spatula and lay on parchment lined cookie sheet.General Baking Tips:Always measure dry ingredients with a dry measuring cup. Measure with dry measuring cups or weigh dry ingredients.Always measure liquid ingredients with liquid measuring cupNever break eggs directly into recipe ingredients. Break eggs into a separate bowl, in case you get any shells, so that you can pull them out.Make sure that you know what temperature your oven is set at. Buy an oven thermometer and check oven temperature regularly.Always check baked goods, like cakes or quick breads with cake tester, placed in center. If the tester comes out clean, it’s done.