Peel and pit the fresh mangoes until you have three cups of fruit.
Puree the mango chunks in a high-speed blender until the texture is completely smooth.
Strain the puree through a fine-mesh sieve if you prefer an extra silky texture.
Pour the chilled heavy whipping cream into a large, cold mixing bowl.
Beat the cream using an electric hand mixer on medium-high speed until it begins to hold stiff peaks.
Add the powdered sugar and vanilla extract during the final stage of whipping.
Fold the smooth mango puree into the whipped cream using a rubber spatula.
Combine the mixtures gently to maintain as much air as possible in the mousse.
Transfer to serving glasses and chill for approximately 2 hours before serving.