Combine 1 1/2 cups sugar, corn syrup, water, and coffee powder in a small Dutch oven. Cook over medium heat, stirring occasionally, until mixture reaches hard crack stage (300°). Remove mixture from heat; stir in soda.
Working rapidly, thinly spread mixture onto an ungreased 15- x 10- x 1-inch jellyroll pan. Let cool completely. Crush and set aside.
Beat whipping cream in a large mixing bowl until foamy; add remaining sugar and vanilla, beating until stiff peaks form and sugar dissolves. Fold prepared crushed candy into whipped cream.