How much to reduce salt when using salted butter?

There is approximately 1 1/4 tsp per pound (US), or a little more than 1/4 tsp per stick (4 oz). For most applications, yes it is fine to substitute and adjust; you can just adjust the “salt to taste” step of your recipe in many cases.

Can I substitute baking soda for baking powder? (Baking Powder is SCD Illegal)

“Yes, as long as there is enough of an acidic ingredient to make a reaction (for 1/2 teaspoon baking soda, you need 1 cup of buttermilk or yogurt or 1 teaspoon lemon juice or vinegar). And remember that baking soda has 4 times the power of baking powder, so 1/4 teaspoon soda is equivalent to 1 teaspoon of baking powder. You can make your own baking powder at home: Sift … Read More