Combine flour blend, sugar, baking powder, and salt in a large bowl.
Add butter pieces and flatten with your fingers until they are all flattened and well combined throughout the dry ingredients.
In a measuring cup, mix the eggs and milk. Add half the egg and milk mixture to the flour mixture and toss with a fork. Continue adding and tossing until mixture is wet enough to stick together, but not overly wet. You may not need the entire egg/milk mixture.
Dump dough out onto lightly floured surface and press with your hands into somewhat of a cohesive mass. Using a rolling pin, press down at different places in the mass into a rectangle about 7 by 10 or 11 inches long. It will be messy and may look like it's not going to come together at all. Use a bench scraper or ruler to "shore up" the sides into a rectangle as best you can.
Using the bench scraper or your hands, do your best to fold the top third of the dough down to the middle, just like you'd fold a letter, and then the bottom third up over the top third. Large chunks may fall off. Just put them back on and continue. Turn the dough clockwise. This is your first turn.
Press and roll dough out again into 7 by 10-inch rectangle, adding a little flour as necessary to keep dough from sticking. Fold again into a letter style. Each time you do this, it will start to look more and more like a dough. Turn clockwise. This is your second turn.
Repeat all of this again 4 more times for a total of 6 times. If the dough begins to get too soft, stop rolling and folding and put in the refrigerator for about 10 minutes, noting which turn you were on.
When completed, your dough should be totally cohesive and look similar to pie dough. Wrap in plastic wrap and allow to chill for at least 1-2 hours before using as desired in any recipes calling for puff pastry or crescent rolls.
For puff pastry or crescent dough recipes, increase the temperature by 50 degrees F for the first 5 minutes of baking and then drop it back to what your recipe normally calls for. This will give the gluten free puff pastry a chance to puff well before baking the rest of the way.