Place pecans on a cookie sheet and brown in a 350 degree oven. Pay attention so they don't burn. I browned for 5 minutes turning a couple of times.
In a small saucepan add the Guinness beer and 2 tbs of sugar. Bring to a boil and reduce the heat until you have 1/2 cup of the beer syrup. It took me about 10 minutes.
In another, larger, saucepan, add the butter, brown sugar, corn syrup, vanilla and salt. Melt down and whisk ingredients well. Add the Guinness beer syrup and stir until combined.
Place the prepared pie shell in a 9 inch pie plate.
Add the browned pecans to the bottom of the pie shell.
Whisk the eggs and whipping cream together in a medium size bowl.
Slowly add a couple of tbs at a time of the syrup mixture, whisking constantly to avoid "scrambling" the eggs. Continue until all the syrup is incorporated.
Pour the egg/syrup mixture over the pecans.
Place the pie in a 350 degree oven for 45 minutes. It will still be "loose" when you remove from oven but will set up in about a half hour.
Let the pie sit for a least an hour or covered overnight before serving.
Notes
If your pie is browning too quickly, place a sheet of tin foil over the top for the last 10 minutes.