Look into the feeders section on how to " grow reptiworms" you'd be amazed how big they get. Your beardie will get lots of nutrition and your wallet won't hurt too much
I bought 1000 medium reptiworms, I put 500 in a cooler with ice to last longer and the other 500 in the small critter cage with whole wheat bread and organic baby food. After a week of feeding them this is how they compare
As for how many to feed, feed as many as they'll eat in a 15 minute period. Branch out to 3x during the day. I feed Dany salad and a few crickets at 6am, more crickets in the afternoon, then the worms at 6pm (always make sure they still have 2 hours to bask before lights go out. Again this is just an example, it's been very successful for my baby girl but use your best judgement
(Dany is 3 months old)