A cup of ice cream contains about 200 food calories. How much power can be produced if the energy in a cup of ice cream is extended over a period of 10 minutes (600 seconds)? Each food calorie is equal to 4,184 joules.

I don't believe your conversion. 1 food calorie = 1 kcal = 4.184 kJ and not 4.184 J.

200 food calories = 200 kCal
Convert to joules where 1 kCal = 4.184 kJ
1 watt = 1 J/s
kilowatts = 200 kcal x 4.184 kJ/kcal x (1/600 sec) = 1.39 kw