To make the butter crunch mixture, melt the butter in a saucepan. Remove from heat and stir in sugar, corn syrup, and water. Cook, stirring occasionally, until the mixture reaches 300 degrees on a candy thermometer. Remove from heat, stir in almonds, and pour out into prepared pan, spreading the mixture with the back of a spoon to fill the pan. Before the butter crunch hardens, but when it is firm enough to handle, turn it out onto a large parchment-covered cutting board and peel away the foil. Allow the butter crunch to cool completely. To finish the butter crunch, wipe the top surface of the candy with a damp paper towel to remove excess butter and allow to dry a few minutes. Have another cutting board or the back of a jelly-roll pan ready to turn the candy over onto. Use a small offset metal icing spatula to spread half the tempered chocolate quickly over the butter crunch. Scatter half the chopped almonds over the chocolate. Cover this finished surface with a piece of parchment paper or foil and place another cutting board or the back of a large jelly-roll pan. Remove top board and paper and quickly spread with remaining tempered chocolate and scatter on remaining almonds (it isn't necessary to wipe the second side because it wasn't against a buttered surface). Refrigerate for 20 minutes to set chocolate. Break the butter crunch into 2-inch pieces. Store candy in a tin or plastic container with a tight-fitting cover and keep at a cool room temperature for up to a week.