Microwave Carmel Popcorn

8 cups of popped popcorn
¾ cup packed brown sugar
6 T. margarine
3 T. light corn syrup
½ t. salt
½ t. baking soda
Put popcorn in a brown paper bag. Combine the brown sugar, butter, corn syrup, and salt in a glass bowl. Microwave on high for 3 mins or until mixture starts to boil; stir at 1 ½ mins. Stir in soda and pour over the popcorn while shaking the bag, then stir it to spread evenly.