Make cupcakes: Preheat oven to 350 degrees, with racks in upper and lower thirds. Lightly butter 48 mini-muffin cups. In a bowl, whisk together flour, salt, cinnamon, nutmeg, and cardamom.
In a large bowl, using an electric mixer, beat butter and brown sugar on medium-high until light and fluffy, 3 minutes. Beat in eggs, one at a time, scraping down sides of bowl as needed. With mixer on low, add flour mixture in three additions, alternating with two additions milk and beating well after each addition.
Transfer batter by heaping tablespoonfuls to cups. Bake until golden brown at edges and a toothpick inserted in center of a cake comes out clean, 15 minutes, rotating pans once. Let cakes cool in pans, 5 minutes, then transfer to wire racks to cool completely.
Make glaze: In a bowl, whisk together juice and confectioners' sugar until smooth; add 1 to 2 drops food coloring if desired. Spoon over cooled cakes.
To make cheerful tinted cakes in several hues, divide the glaze into small bowls and stir 1 to 2 drops food coloring into each.