Procedure:

Combine flour and salt.

Add some ice cubes and make ice cold water.

Take chilled butter, cut into cubes.

Add it to the flour and with finger tips rub it into the flour.

Our intention is to break down the butter to pea sized pieces.

Now add ice cold water little by little and bring the dough together. Do not knead. Just bring it together.

Take a parchment paper, transfer the crumbly dough on it, shape it into a thick rectangle.

Cover and place it in fridge until firm to touch (minimum 30 minutes)

Now take it out, dust some flour on top and roll it into a thinner rectangle. The sheet would be very rough.

Using a dough scraper, make two folds  like a letter fold. Now cover and refrigerate until firm.

Repeat it two more times and you will see that the sheets smoothness improves a lot during next fold.

After the third and final fold, refrigerate until firm.

Dust with flour and roll it into a thin rectangle.

Cover and rest in fridge until firm. Cover the tray with cling film to avoid drying it out.

Now make the paper cones or use the metal cones.

Take out the dough, cut it into thin stripes using a pizza cutter.

Take the cone and wrap the stripes on the cone starting from the bottom. The stripe should overlap while wrapping.

Once all the stripes are done, cover the tray with cling and let it sit in fridge overnight.

Next day, preheat oven to 200°C.

Take the tray out, apply milk wash and immediately keep in oven.

Bake it for 30-40 minutes or until golden.

Take it out, with the help of a spatula, release the cones from the tray and allow them to cool completely.

Wriggle them out of the cone and set aside.

Whip the sweetened cream with vanilla until stiff peaks form.

You can also beat some cream along with room temperature ganache and fold in some more cream to make chocolate cream filling.

Fill the cream in piping bags.

Melt some chocolate and apply it inside each cone using a brush.

Now fill the cones with cream. 

Your cream rolls are ready.