I am new to the forum. I have a large egg.
Just got finished last month with my eggtension to my outdoor kitchen--only took 9 months. Framed it with steel studs on top of trex board for moisture isolation, added hardie backer/durarock to the steel frame and then had professionals do the countertop and stone work. Put a drop-in cooler beside of the egg--good for holding pulled pork hot for hours when the cooking completes early and for chilling drinks otherwise. The single door allows egg vent access, and the double doors allow access to storage and the storage beneath the cooler. The back of the countertop extends into a wrap around bar. Not the most attractive patio umbrella, but a core bit was used to form a hole for it in the patio.
Solved some unique problems (for me) in this build way relating to how to frame curved walls with steel studs, how to "curve" durarock to fit the curved walls, how to seal the egg to the countertop (due to the region beneath the egg counter being closed), how to install a drain to the cooler beneath the patio without trenching the patio, how to properly support a large granite countertop overhang and how to solve a condensation problem when cooler is packed with ice. Finally time to cook!