Melt 1 cup unsalted butter in a light-colored saucepan over medium heat, stirring until the bits turn golden brown and smell nutty. Pour the butter and browned bits into a mixing bowl and cool for 10 to 15 minutes.

Whisk 1 cup brown sugar and 1/2 cup granulated sugar into the cooled brown butter. Whisk in 2 large eggs and 2 teaspoons vanilla extract.

Stir in 2 cups all-purpose flour, 1 teaspoon baking soda, 1/2 teaspoon baking powder, and 1/2 teaspoon salt until no dry flour remains. Add 1 teaspoon cinnamon if using. Fold in 1 1/2 cups old-fashioned oats, 1 cup dried tart cherries, and 1 cup chocolate chunks or chips. Fold in 1/2 cup nuts if using.

Scoop the dough into 16 tall 1/4-cup mounds on a parchment-lined sheet. Chill for 30 to 60 minutes, or freeze the mounds for 20 to 30 minutes until firm.

Preheat the oven to 350°F. Arrange 6 chilled 1/4-cup dough mounds on each parchment-lined baking sheet, with room between them. Bake for 14 to 17 minutes, until the edges are set and golden and the centers look slightly soft. If baking from frozen, add about 1 to 2 minutes.

Cool the baked cookies on the pan for 10 minutes, then transfer to a wire rack.