First: know the wattage of your microwave. This recipe works best on a 1000-watt microwave. If your microwave is less than 1000-watts, you may need to increase the cooking time. If it is higher than 1000-watts, you may want to decrease the cooking time.
In a large plastic microwaveable bowl, add in the sugar, heavy cream, salt, butter, and pecans. Do not stir. Microwave on HIGH power for 3 minutes. Remove from the microwave and stir for 30 seconds. Microwave again on HIGH power for another 3 minutes. Remove from the microwave and stir for about 45 seconds. Lastly, microwave once more for 2 minutes and 30 seconds on HIGH power.
Remove from the microwave and add in the vanilla. Beat the mixture with a wooden spoon, stirring vigorously until mixture becomes thickened and cloudy/dull in color, about 2 minutes or so.
Working quickly, drop heaping spoonfuls of the pralines onto a parchment-lined baking sheet. Allow pralines to cool and set at room temperature before storing in an airtight container.