Preheat oven to 350F. Sift together flour, baking powder and salt; set aside. Put butter and 1 1/2 cups sugar in the bowl of an electric mixer fitted with the paddle attachment. Mix on medium speed until pale and fluffy, about 3 minutes. Mix in eggs. Reduce speed to low; gradually mix in flour mixture. Add in cinnamon chips.

Stir together cinnamon and remaining 3 tablespoons sugar in a small bowl. Shape dough into round balls; roll in cinnamon sugar. Space 3 inches apart on baking sheets lined with parchment paper or a Silpat.

Bake cookies, rotating sheets halfway through, until edges are golden, 12 to 14 minutes. Don't overbake. Let cool on cookie sheet for a minute or two, then transfer to a cooling rack.