Soak almonds in hot water for 15mins. Peel off the skin and toast the almonds in a pan till slight brown spots appear here and there. Cool down.
Take almonds along with a tablespoon of granulated sugar in a mixer and grind it to a semi fine powder, set aside.
Scrap the lemon outer skin to take lemon zest.
In a mixing bowl, take flour, cinnamon powder, salt and lemon zest. Whisk it well.
Carefully separate egg yolk and keep aside.
In a mixing bowl take butter, add sugar to it beat it well using a hand mixer or with a whisk. Beat well till the mixture becomes fluffy at least for 2mins.
Add vanilla essence, powdered almonds and eggs. Beat it for 2mins.
Finally add flour. Beat it till the mixture comes together. Bring together with your hands to form a smooth dough.
Wrap in cling film and chill the dough at least for 30mins.
Preheat oven at 180 deg C for 10mins. First get ready with cookie cutter, you need small and big cutters like these.
I used only half dough now and stored the rest for later use. Now lay butter paper or parchment paper, place the dough and again place another butter paper and roll the dough to 1/4 inch thickness.
Take your cookie cutter, dip it in flour. Cut, first with bigger cutter then cut with smaller cutter in the center.
Collect the scraps and then roll again, repeat to finish until the entire dough gets over. Arrange it in a baking tray.
Bake in preheated oven at 180 deg C for 10-12 mins or until the edges starts to turn golden brown. Do not be tempted to bake more the cookies will become hard .Now take jam and place in inside simmering water for few mins so that the jam turns gooey and spreadable.
Get ready with icing sugar too. First separate the cookies with hole and without hole and place separately.
Place the cookies in a plate without hole upside down. Spread jam on it.
Now take the cookies with a hole, sieve icing sugar on it.
Now take the hole cookies and place it on the cookies with jam. Now your cookies are ready.
Linzer Cookies keeps well for about 2 weeks in room temperature itself!