You can use sugar or Splenda (for a sugar-free version), and whatever type of plums you want. I used a combination of red plums and plumcots here.
Fresh PLUM PIE
One or 2 pie crust(s)
Filling: about 8-10 fresh plums
1 cup granulated sugar ~or~ plain white Splenda (NOT baking blend)
2 TB corn starch…………………………..…1/2 tsp. salt
1 tsp. ground cinnamon………………….....1/4 tsp. ground nutmeg
1 egg, lightly beaten (for egg wash)……... optional: cinnamon sugar
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Preheat oven to 400. (I always spray the bottom of my 8” or 9” pie pan lightly with non-stick baking spray {which contains flour}, so that 1st piece doesn't stick.) Roll out the crust(s) and put bottom crust in prepared pie pan. (TIP: If you only made enough dough for 1 crust, you can use the scraps to make a few lattice strips to put across the top edges, or use a cookie cutter to make decorative shapes on top ~ seal at the edges of crust.) Set aside.
Remove pits from the plums, and slice them into a large bowl.
In another bowl, whisk together all the dry ingredients ~ then add them to the plums and mix well. Put plum filling into the bottom pie crust. If you’re using a top crust, put it on and seal at the edges. Brush the edges and any crust on top with the beaten egg for a golden crust. (I like to sprinkle some cinnamon sugar over cut-out pie crust pieces on top.) Lightly set a piece of foil on top and put the pie pan on a rimmed baking sheet to catch any run-over during baking.
Bake for 40-50 minutes. (I baked mine for 40 minutes ~ then took off the aluminum foil sheet and baked another 10 minutes to get the crust browner.) Let it cool in pan about 10-15 minutes before slicing. My husband likes it with lots of Cool Whip.