Mix the dry ingredients first. At this point, you can add to the dry mix raisins, seeds, oats… It should total 750 gr, in the proportions you want (I like doing 450 gr wholewheat, 250 gr white, plus 50 gr oats).
Add a couple of tablespoons of oil to the buttermilk, mix it well and let it sit before mixing with the rest of the ingredients. Knead with a spoon until you get a firm though which still sticks a bit in your fingers. (If you don't have buttermilk, you can use milk and add a couple of tablespoons of vinegar or lemon juice plus the oil instead.)
Mix all of the ingredients but rather quickly as not to make the dough too warm and soft, refrigirate it before use.
Be careful to use warm water so the ingredients bond more firmly and make the dough softer.
Mix all of the ingredients into a firm ball and rest for 30 minutes under a kitchen cloth (you can halve the dough so it will be easier to strech it thinly later on). Then role out the dough into about a fingers width of a sheet and spread oil over the surface to prevent tearing.
Strech the dough over the surface of the table as thinly as you can (make sure you put a cloth underneath with lots of flower so it wont stick to the table). Cut the dough into about ten sheets that are slightly larger than the base of the baking dish.
Role out the base dough into a thin sheet and spread it over the bottom of the baking dish, fold and lift the ends of the dough and press them against the walls of the dish making a bowl.
Then put a sheet of “pulled” dough over it and spread your first filling - the poppy seeds. Spread a modest amount of the sour cream topping and sugar.
Then come the next sheet and the grated apples which you season with cinnamon (grandma used to have a heavy hand when it came to this but use as much as you see fit) and sugar.
Now comes another layer with the walnuts and then cottage cheese. You cover both with the cream topping but don’t hold back with the cottage cheese, make sure that bad boy is nice and moist. Also you can mix the walnuts with the cream beforehand so they’ll be easier to spread.
Repeat all four layers and cover the whole thing with two sheets (spread the butter and some cream carefully between the layers so they won’t get stuck into a single hard sheet).
Before putting it in the oven generously cover the top with, you guessed it, more cream.
Slowly bake for about an hour (this part is really vague so I guess at around 180 degrees).