I made this pizza on the grill without a pizza stone.  I normally use an amazing new stone from Emile Henry, upon which you can build the pizza directly, and put it right in the oven or grill, without pre heating.  The crust comes out nice and crunchy without the transfer of the dough to the stone – MUCH easier!    Anyway, the pizza was fabulous – and pretty easy to make.  Pre grill the pineapple, pancetta and scallions, so once the crust starts, it goes quickly.  I have a 4 burner grill, so the indirect heating method works pretty well on it.  Just keep the outside two burners on high, and place the crust in the middle.  I cheated a little and kept the middle two on low to speed the process a bit…. It really depends on the grill you are using.  So anyway, here is the process:
Ingredients:
1 fresh pineapple, peeled, cored, and sliced into ½ inch ring slices ( you will be using 5 or 6 slices)
½ lb pancetta, cut thick ( about 5 slices)
2 Vidalia onions sliced thin
2tbs olive oil
2 tbs butter
½  10 oz package Queso Fresco, crumbled
6 scallions, root ends cut off, grilled, then rough chopped into about 1 inch pieces
1 ball fresh pizza dough
2 tbs flour
1 tsp red pepper flakes
Instructions:
In medium fry pan, place slices of pancetta so they do not overlap.  Cook until just becoming crispy, about 3 minutes per side, then set aside.   Drain most of the grease.  In the same pan, melt butter, add olive oil , then add onions, and sauté until golden brown – about 5 – 7 minutes.  Set onions aside.
Brush pineapple slices with butter, and scallions with olive oil.  Grill until pineapple has nice grill marks, and scallions begin to blacken – about 5 or 6 minutes or so.  Set aside.
Pre heat grill to 400 degrees, the shut down middle two burners.  If a 3 burner grill, shut down 2 of the three burners.
Spread flour over rimless cookie sheet or cutting board.  Roll out dough until it is a fairly even 14 inch circle or so.  Place on grill, and close cover.  Grill covered for about  5- 7 minutes, depending on your grill, or until bottom of crust begins to crisp.  Transfer crust to rimless cookie sheet.
Spread caramelized onions over entire pizza.  Crumble Queso Fresco cheese over onions.  Place the pineapple slices evenly around the pizza, and top each with a slice of pancetta.  Top everything with the grilled scallions – roughly chopped, and sprinkle with red pepper flakes.
Return pizza to grill, and grill until crust edges are crisp – about 20 minutes or so, again depending on the grill you are using. 
Cut pizza into slices so each slice has a piece of pineapple….. and enjoy!