Peeps are good when properly aged....yes, at least a month, usually for six months or more in a properly dehumidified cellar at 67 degrees, but remember to open the package slightly for good aeration. Otherwise they do not reach the chewy state that is desired.
Now, if you are a feeling like you just HAVE to eat them now, there are two (and only two) proper and acceptable options:
The first is quick and dirty: Place a pair of peeps in the microwave for 10-15 seconds (depending on the wattage of your microwave). They will expand to 3 or 4 times their normal size, which in itself is pretty funny to watch. Make sure you use a microwave safe bowl, and allow them to sit for another 5 seconds (we don't want any skin ripping as you eat super heated sugar)

The other, usually more preferred method, is to treat them as a regular marshmallow: Roasted over a campfire.

When you place them on the appropriate roasting stick or roasting fork, leave a little bit of room between each peep to allow for proper heat distribution. This also keeps the exterior sugar of one peep from sticking to its neighboring peep. Now, be sure not to set them too deep into the fire, as this can cause scorching of the exterior sugars.You only want to caramelize the the sugar coating. They will expand a little bit, but don't leave them too long or they could fall off the roasting stick, then you have to start all over. Once you have roasted the peep to your desired state of done-ness, carefully remove from the roasting stick with your fingers and eat. Any use of civilized tools such as a fork and/or plate is unacceptable. Be careful to not allow your

near the roasted peep, as it could injure the

and it's tender mouth. Also, and this is VERY important: It is against peeplaw to put the roasted peeop on a s'more. This would be cause for punitive action up to and including revocation of your peep roasting card, and in severe/repeated cases; notification of proper authorities causing the subsequent visit of Billy-Klubb for obligatory peepberry punching.
thus sayith the first book of peep.