Preheat oven to 375 degrees. Spray ramekins with cooking spray.
melt butter and chocolate chips together
in a mixing bowl, whip the eggs and add the sugar (this can be done by hand or with a mixer)
add vanilla and flour and mix well
then gradually stir in the chocolate mixture
pour into the ramekins filling about 2/3 full
place ramekins on cookie sheet and put in oven
bake for about 15-17 minutes, testing to make sure they are still gooey in the middle (don't over cook them) but not too runny.
Serve warm with vanilla ice cream or whipped cream!