The flour she starts with
Everything here comes out of one bag. Lynn uses the King Arthur unbleached, not bromated all-purpose flour that Travis buys. Her reason for making the rest herself is money: she says the small bag runs around six dollars, and buying self-rising, bread and cake flour separately gets expensive when you go through as much of it as she does. She believes the small bag is a four pound size but does not say for certain.
Travis measures out the exact amount that fills her flour container and vacuum seals it so nothing can get in and it stays fresh. The trick she shows for that is laying a paper towel over the top of the flour so the vacuum sealer does not suck the flour up into it. Sealed, the flour feels real hard, but she shows that once you open the bag and the air gets back in, it goes right back to soft flour.
Self-rising flour
For this one she needs baking powder, one cup of flour and some salt, and she uses pink salt because that is what they like. The amounts are one cup of all-purpose flour and one teaspoon and a half of baking powder, plus a fourth of a teaspoon of the pink salt. The baking powder she reaches for is her own homemade batch kept in a recycled can.
Mixing is not quite enough on its own. She stirs it together and then sifts the cup of flour with the baking powder and salt so everything is combined, using a small sifter here and a bigger one that turns when she makes a larger batch at one time. Then she runs it through the sifter a second time, and that is self-rising flour out of all-purpose.
Bread flour
This is the one she reaches for when she is making pizza dough, yeast rolls or a loaf of bread. Measuring matters more here than anywhere else: she will not dip the cup down into the flour, because scooping it out that way packs the flour into the cup. Instead she spoons flour in over the top and levels it off without packing it down.
From that level cup she takes two tablespoons of the flour back out, leveling the spoon as she goes. In their place go two level tablespoons of cornstarch. She gives it a mix and says that is the same product you would buy as bread flour, then sifts it like the last one so the cornstarch gets combined all through the flour.
Cake flour
Cake flour is what she uses for cookies, cakes and pastries, and it is the one that takes patience. Rather than measuring a cup and removing part of it, she measures out fourteen tablespoons of all-purpose flour, leveling each one. Then she adds two tablespoons of cornstarch, leveled off too.
Mixed and sifted, that adds up to the one cup of cake flour your recipe is asking for. She sifts this one for the same reason as the others, to get the cornstarch worked all the way through. What comes out is soft and fluffy, which she credits to not packing the cup and to measuring the fourteen tablespoons exactly.
Using them in your recipes
Nothing about your recipe changes. Lynn is clear that when you use these flours you still follow the exact recipe you are making your rolls, cakes or pastries with. The homemade flour is a straight swap for the bag you would have bought, not a new recipe.
By the end she has cake flour, bread flour and self-rising flour all out of the one all-purpose bag, which is the whole point of keeping only one kind on the shelf. The step by step is on the video page, the same flour goes into her homemade pancake mix, and if a batch behaves oddly you can ask Lynn.