Cheapest desserts to make that sell?!

Rice Krispy Squares are always popular and very inexpensive to make.

Sugar Cookies aren't to expensive to make and they are also really popular. They can be a PITA but if you just do round drop cookies instead of rolling the dough out and cutting out shapes they're a lot easier and just as delicious. Make a nice powdered sugar frosting in pretty colors and people will gobble them up.

Cookies, brownies, You can buy some cookies and brownies put them in the microwave for 4-10 sec and put some ice cream on it..

snow-cones. Block ice is cheap, the paper cups are cheap and the flavored syrup is cheap.

rice krispy treats You could drizzle white chocolate on top..
brownies peanut butter frosted..Homemade

Popcorn!! The smell will have people comming from everywhere to buy it!!

rice crispy treats
sugar cookies
cupcakes