You may want to experiment with adding flavourings to the cheese, such as chopped cilantro, epazote or chives. But I think there is a lot going on here. The point is really the taste of the padron pepper itself, offset with cheese while both are enrobed in chipotle sauce.
The rellenos are best straight from the frying pan. But if serving for guests, it may be easier to fry all the peppers and drain, then re-heat in a hot oven just before serving.
To make the chipotle sauce
- Chop the onion and sweat in a couple of glugs of good olive oil on medium high heat for 5 minutes. Chop the garlic, add to the onion, and continue to sweat for 10 minutes (without colouring). Add the vinegar and stir, and then add the stock and herbs. Bring to a boil then turn down the heat and simmer for 10 minutes. Add the chipotles or paste and simmer for a couple of minutes, then add the tomatoes and bring back to a boil and simmer for 10 more minutes.
- Next, blend the sauce. Remove the bay leaves, and blitz with a stick blender or allow to cool, and then blitz in normal blender. Return to the pan and heat gently for 5 minutes more.
- Adjust the seasoning.
To make the chilli rellenos
The traditional way with chilli rellenos is to char pablano chillies all over then put in bowl with cling film to steam and then peel off the charred skin. This is the same method used for preparing roasted red peppers, however with rellenos the chillies are kept whole. Padron peppers have thin skins. They will ‘eat’ much better if pre-cooked under a grill rather than stuffing and frying fresh. The thin skin will peel off these small peppers, just like the larger ones, but it is not necessary to do this all around the pepper or for all of the peppers – its flesh is not thick enough and it may damage the pepper.
- Put the peppers under a hot grill. Watch them carefully so they do not burn or over-cook. When one or two start to pop or the skin blackens, turn them over. Cook them all evenly. Place in a bowl, cover with cling film and let them cool.
- Take each pepper and carefully remove any skin that will be easily removed without damaging the pepper. Then with a small sharp knife, cut vertically down the pepper, from just below the stalk to just before the bottom of the pepper. Next cut delicately under the stalk to remove the cluster of seeds at the top of the pepper. This is easier in two stages turning the chilli once to cut either side of the cluster. Next, remove the seeds by pulling gently down the top part of the pepper. Use scissors or a knife to cut the veins connected to the seeds and do this before pulling the veins down any further – pulling the veins out of the inside of the pepper will damage the pepper’s skin.
- Mix the two cheeses in a microwave-safe bowl and microwave for 20 seconds at high power. Mould the cheese into a rough shape smaller than the padron pepper. Then delicately fill the peppers with cheese. Although initially very fiddly, it becomes easier as you make your way through – try working the cheese in stages into the cavity rather than pushing it all in at once. Use a small spoon or knife to bring the sides of the cut pepper together. Do not worry if you over-fill a little. Roll the peppers in your palms to shape the peppers and ensure the sides are as near as possible.
- Pour oil into a large frying pan – ideally with high sides – until it is about 2.5 cm deep or safely below the rim of the pan. Heat to 180C.
- Just before frying, make the batter. Separate the eggs into two bowls. Add a pinch of salt to the whites and 2 tsp flour to the yolks. Whisk the whites with an electric mixer to stiff peaks. Then beat the yolk until light and airy. Beat the the yolks into the whites just until mixed. This batter will collapse soon after making, beat again if necessary, but it is best to make just before frying.
- Work in batches. Dust the peppers in flour and dip in the batter and then into the frying pan.
- You will notice that the peppers form very effective little boats and will resist turning over. Either force them with tongs (which may damage the batter or pepper) or spoon hot oil over the top of the peppers. Cook until lightly browned all over and drain on plenty of kitchen towels.
- Serve immediately with the chipotle sauce and cilantro garnish, or store for a couple of hours and re-heat in a hot oven just before serving.