Preheat oven to 325 degrees F. Line a large baking sheet with parchment paper or if you prefer, use an ungreased insulated sheet such as an AirBake.
Mix together the flour and coconut and set aside.
In a large saucepan, melt the salted butter. Add the corn syrup and brown sugar and stir until smooth.
Remove from heat and stir in the vanilla and the flour/coconut mixture. Allow the mixture to stand and thicken for about 10 minutes. You can leave it in the saucepan or pour it into a bowl so it will cool quickly.
Scoop up heaping teaspoons of dough and shape into neat rounds. Press the centers down just slightly so they'll bake more evenly. Set on the tray leaving about 3 ½ inches between the cookies so they'll have plenty of room to spread.
Total bake time should be between 15 and 20 minutes, and you'll need to keep a close eye on the cookies, rotating the pan halfway through. Start checking at 15 minutes. Pull cookies when the outsides are browned and the insides are still just a little pale.
Let cookies cool on the baking tray for about 2 minutes, then carefully transfer to a wire rack to cool and crisp. Give them time to completely cool before tasting. If using parchment, slide the parchment off the tray and onto the counter and let cool completely before peeling off.
This is optional, but if you have some Maldon salt flakes a sprinkle or two is a nice addition.