Line 3 large baking sheets with parchment paper. Preheat oven to 375ºF (190ºC).
Whisk together flour (2 1/3 cups), baking powder (2 teaspoons), and salt (1/2 teaspoon) in a medium mixing bowl.
Add the butter (10 tablespoons) and sugar (1 1/4 cups) to the bowl of a stand-up mixer. Cream together on medium speed until light and fluffy, about 2 minutes. Scrape down the bowl halfway through.
Add milk (2 tablespoons) and mix until the mixture is well blended.
Add eggs, 1 at a time, beating just until the yolk disappears into dough.
Mix in vanilla (1 teaspoon).
Gradually add flour mixture, 1/4 cup at a time, mixing until the flour is well incorporate but don't over beat. Remove bowl from mixer.
Add chopped cherries (1/2 cup), dates (14), and pecans (3/4 cup), and fold in with a large rubber spatula.
Use a medium cookie scoop (#40 portioner holds 1.5 T of dough) to portion the dough, then roll in the cornflakes (2 1/2 cups). After the balls of dough are coated with cornflakes, roll them between your hands to firm up the ball.
Gently press a cherry half on top of each cookie. Use your hands to tighten up the shape.
Arrange on a baking sheet 2 inches apart. Press half a cherry into the top of each cookie and press gently (the whole cookie will flatten slightly)
Bake cookies in the preheated oven until they are set, about 10-12 minutes. Cool on baking sheet for 5 minutes then remove to a wire rack and cool completely.