Soft butter beat with a mixer with sugar and salt. important! the butter should be soft, not melted. I usually leave it overnight at room temperature and in the morning bake cookies

Add sour cream and beat again for a couple of minutes

In three steps, add the flour. first beat with a mixer, then knead with your hands until the dough no longer sticks to hands. You may need a little more flour. but don't overdo it.

In the end, should get this ball. dense but soft. if you press it, your finger easily leaves an imprint on it. Leave it to rest for 30 minutes at room temperature

Roll the dough 3-4 mm thick and cut into squares about 7x7 cm from scraps again roll out the dough again and cut out the squares and so until all the dough. Of this number ingredients I got exactly 25 squares

In the middle of each square, put the jam. I love citrus and therefore took the jam Mahe lemon and orange. But you can take any flavor you like. Importantly, the jam was thick and did not spread.

Join the end squares to make the envelope. Grease cookie is not needed. Spread on a baking sheet, the laid parchment paper and bake at a temperature of about 180-200 degrees (here all individually. look at your oven) for approximately 15 minutes. to very lightly Browning. If in the process of baking the envelope opened ( I was 2), then when you get the pan out of the oven, simply press the ends of the envelope with a fork. Cookies soft and it is very easy to do.

After cookies are completely cooled, lightly sprinkle it with powdered sugar. p.s. the next day it becomes even tastier. creamy taste even more pronounced, and the jam stretches like taffy. p.p.s. Instead of envelopes a layer of rolled dough can be lubricated entirely with jam, roll it up and slice in the form of snails. Bon appetit!