I purposely waited awhile before introducing peas to Buttercup. Because they're round and relatively hard I figured they could pose a choking hazard for inexperienced eaters. I have been looking for signs of readiness. Buttercup has a well developed pincer grasp these days and is able to isolate and pick up tiny pieces of food. Also, she rarely gags and seems to have really good control over the food she puts in her mouth. So, peas made their debut into Buttercup's life.
I poured boiling water over the peas and let them sit for a few minutes. Before serving them, I squeezed each one til they popped, as an extra safety precaution against them slipping down Buttercup's "wrong pipe."
Buttercup loved them. She ate them in the same manner she eats breakfast cereal (and beans and raisins), though the peas proved to be a bit slipperier than other small foods she's had.
PROS: great easy vegetable
CONS: a little slippery, make sure your little one is ready for small foods (has pincer grasp)