In a large skillet over medium-high heat, brown ground beef until crumbly. Add chopped onion and a pinch of salt and pepper, stir to combine and saute for 5 minutes.
Sprinkle arrowroot powder (or flour) evenly over beef and onion mixture. Pour beer into pan and reduce heat to low. Stir until mixture starts to thicken (around 2 minutes).
Add grated cheese and stir until melted (around 2 more minutes). Top hamburger bun with a hefty scoop of sloppy joe mixture and garnish with chopped fresh chives. Enjoy!
Notes
I use a gluten-free hamburger bun to make this dish GF!