Mix the softened butter with the sugar until very frothy, then gradually add an egg, continue beating the mixture, add the vanilla flavor and lemon zest, then stir in the flour. Gradually stir in the oat flakes, then fold in the walnuts and cranberries. Place small heaps with a spoon on a baking sheet lined with baking paper and flatten them lightly with a fork.
Approx. 70 cookies (= 2 to 3 trays) can be prepared from the above ingredients. Bake the cookies at 180 ° C top / bottom heat for about 12 - 15 minutes. You`re done when they`re light brown. The second and third tray usually take less time - just check after 10 minutes.
Let the cookies cool down on a cake wire, then store them in a cookie jar.
Instead of cranberries, the cookies can also be prepared with other dried fruits (chopped up!) And without chopped walnuts.