What the heck are they? they are the buds of elephant garlic. I have always found elephant garlic to have an unpalatable aftertaste, but the buds are fantastic. They have a fairly similar texture to asparagus with a very garlicy flavor.
Nutrition: I have no idea, I can't find the nutritional information anywhere.
How do I cook them: I have found that hot dry cooking methods work well. Rub them with a little olive oil and salt and popped into a 425 degree oven till they are brown and delicious. They work okay on the grill, but you have to be careful that the buds at the top do not dry out too much as they become papery.
How do I pick a good one: like asparagus you want to look out for rot in the middle of the bundle. Bright green is good, they will dry out from both ends so keep an eye out for any yellowing as it is a sign that they have dried out (a little drying of the tips is fine, but too much is too much).
When are they in season, where do I get them? RIGHT NOW! Late spring early summer. They are available all over the PNW, but I have seen them at whole foods and similar specialty grocers in other parts of the country.