Padron Chilli Peppers are the variety traditionally used in Spanish tapas. They are used whilst green & immature and are very mild, however 1 in 10 may be hot - a game of chilli roulette!!
Padron chilli peppers are cone shaped and slightly wrinkled. The pods are green when immature & harvested at 3cm long and mature when red at about 10cm long by 4cm wide. Mature red ones will reach between 3,000 - 12,000 SHU so of mild to medium heat.
The chilli plants can reach 1-1.2m tall and will continue to produce peppers so long as the pods are regularly picked.
Spanish Tapas recipes usually roast them in olive oil and sprinkle with salt but they are excellent fresh/for stir-fries or stuffing.