Strawberry Margarita Squares

1-1/4 cups crushed pretzels
1/4 cup (1/2 stick) butter or margarine, melted
1 can (14 oz.) sweetened condensed milk
1 cup pureed strawberries
1/2 cup lime juice
1 tub (8 oz.) COOL WHIP Whipped Topping, thawed

Mix pretzel crumbs and butter in 13x9-inch pan; press crumb mixture firmly onto bottom of pan. Refrigerate until ready to fill.

Mix sweetened condensed milk, strawberries and lime juice in large bowl until well blended. Gently stir in whipped topping. Pour over crust.

Freeze 6 hours or overnight. Let stand at room temperature 15 minutes before cutting to serve. Garnish with sliced strawberries.