Preheat oven to 300 degrees. Grease and flour (with matzah meal on Passover) a 9 or 10-inch springform pan.
Whip the egg whites until stiff, up to 15 minutes (or about 5 minutes in a Kitchen Aid mixer). Gradually add the sugar and whip a few more minutes. Add the vinegar and vanilla and whip until it looks like marshmallow.
Spoon the egg white mixture into the pan and make the sides a little higher than the middle. Bake for 50 minutes, shut off oven, and leave the pan in the oven overnight.
When ready to serve, whip the cream until soft peaks form and fold in the diced strawberries. Gently break off the top crust of the meringue and set the pieces aside. Remove the rest of the meringue from the pan by running a knife several times around the sides and then releasing the pan. (You can gently move the meringue to a platter by running a knife underneath it and transferring it with a spatula, or just place the meringue still attached to the bottom of the springform pan directly on the platter.)
Spoon the cream and strawberries on top of the meringue base and then place the reserved crust pieces back on top. Use a serrated-edged knife to carefully cut the meringue into serving pieces.