Line a 15- x 10-inch jelly roll pan with heavy duty aluminum foil.
In a medium saucepan melt ¼ cup butter and pour into the prepared pan and spread to coat the foil.
Melt the remaining butter and stir in the Splenda® Brown Sugar Blend. Bring to a boil over MEDIUM heat. Reduce heat and cook for 2 to 3 minutes, stirring occasionally.
Remove the pan from the heat and stir in the Splenda® Sweetened Condensed Milk. Mix well.
Spread the toffee mixture evenly over the crackers.
Bake for 9 to 10 minutes until mixture is bubbly and golden brown.
Once out of oven, immediately sprinkle with the chocolate morsels and let stand 5 minutes until the chocolate has melted. Then, spread the chocolate into an even layer over the crackers.
Sprinkle with the nuts and lightly press them into the melted chocolate.
Allow to cool in the pan for 30 minutes and then refrigerate until the chocolate is set.
Carefully peel off and the foil and cut or break the cracker toffee into pieces.
Store the cracker toffee in an airtight container in the refrigerator for up to 2 weeks.