Preheat oven to 350°F (175°C). Grease a large baking dish.

In a large bowl, combine mashed sweet potatoes and softened margarine.

Mix until well blended.

Add eggs, vanilla extract, lemon juice, and sugar to the sweet potato mixture.

Pour in the evaporated milk.

Add cinnamon and salt.

Mix all ingredients well.

Stir in chopped pecans and flaked coconut.

Spoon the sweet potato mixture into the prepared baking dish.

Bake for 20 minutes or until heated through.

Remove from oven and arrange miniature marshmallows evenly over the top.

Return to the oven and bake for about 3 minutes, or until the marshmallows are puffed and golden brown.