I have been using this method for 30 years, no more thin runny whipped cream and your whipping cream will hold up for days this, is fabulous on cakes - for 2 cups whipping cream use 2 tsp gelatin in 2 tbsp cold water.
1 teaspoon unflavored gelatin 4 teaspoons cold water 1 cup heavy whipping cream (35%) 1⁄4 cup sifted icing sugar (confectioners sugar) In a small pan, combine gelatin and cold water; let stand until thick. Place over low heat, stirring constantly, just until the gelatin dissolves. Remove from heat; cool (do not allow it to set). Whip the cream with the icing sugar, until slightly thick. While slowly beating, add the gelatin to whipping cream. Whip at high speed until stiff.