In a bowl combine the flour, salt, baking powder, and baking soda. Whisk until incorporated.

In another bowl, whisk together the butter, sugar, and vanilla until light and fluffy.

Add in the eggs, and mix until well combined. Fear not if the mixture looks sort of clumpy and separated, it comes together when you add the flour.

Gradually add in the flour mixture and switch to a rubber spatula if necessary. You can add 1/4 cup more of flour if needed.

Divide the dough into two even balls and wrap in cling-film. This is so that a skin does not form on the dough, and it remains smooth.

Chill the dough for an hour or two, or until slightly firm.

Unwrap the dough dust with flour and, roll to a 1/4 inch thickness on a floured surface. Cut the dough with cookie cutters, or roll the dough into a log and slice. Keep flouring the tops to prevent it from sticking.

Place this dough onto a parchment paper lined baking sheet.

Bake the cookie cut outs in a 200 C or 400 F preheated oven for 4-6 minutes - 6 works fine for me, but keep an eye on them as you may need to bake them for a little longer.

Whisk together the butter and milk. The softer the butter, the easier this step is. Melted butter is probably the best.

Add the vanilla and confectioners' sugar, beating until fluffy and smooth. Add more milk for a thinner consistency or more sugar for a thicker one.

Color the icing with your food dye if you'd like.

Spread the icing onto the cookies and top with sprinkles. Wait till the icing has hardened (approx. 1 hour or less if refrigerated) before stacking or serving. (NOTE- the dough keeps well in the freezer for up two months or in the refrigerator for a couple days).

For the icing (NOTE- I used enough for 30 cookies as I freezed one of the balls. The recipe below is for 60 cookies.)