In a large bowl, whisk cake mix, flour, and sugar. Stir in melted butter, vanilla, milk, and sprinkles. The mixture should be moist and be able to hold its shape easily when formed.
Using a cookie scoop, form mixture into even balls and refrigerate 20-30 minutes.
In the meantime, melt chocolate in a double boiler or slowly in the microwave. Using a fork, drop one of the cake batter truffles into the chocolate and roll around to coat. Tap off the excess gently and transfer to a cookie sheet lined with wax paper.
Top with more sprinkles, if desired.
If you are worried about consuming raw flour simply toast your flour/cake mix in a 350-degree oven for 5 minutes on a cookie sheet. This might give it a slightly nutty flavor but you won't have to worry about unwanted bacteria.