In a large bowl, beat together butter and sugars until well creamed. Beat in eggs, pumpkin and vanilla. In a separate bowl, mix together the flour, baking powder, baking soda, cinnamon and salt.
Add dry ingredients to the wet and stir until combined. Mix in toffee bits.
Preheat oven to 350 F. Drop dough by rounded tablespoons onto cookie sheets. Bake for 13-14 minutes or until edges are slightly browned. Do not over bake. Let cool completely.
To make the glaze, brown the butter in a saucepan over medium heat, stirring occasionally. Let cool. Mix in the powdered sugar, cream and as much water as necessary to make a smooth glaze. Drizzle, pipe or spread the glaze over cooled cookies. Cookies will be moister the second day.