if you don't happen to find some roasted almond flakes in your pantry (from any previous baking adventure) ... Roast the almond flakes in a pan for some minutes. Watch continuously - don't burn the mess!
Mix sweetened condensed milk, Greek yoghurt, summer jam & almond flakes w/ a spoon.
OPTIONAL: Add the liqueur!
Fill the mess in a container fit for the freezer.
Let it rest for about 5 h in the freezer; mix every 60 min w/ a spoon.