Garlic Butter: Use a fork or spatula to combine the garlic butter ingredients in a medium mixing bowl. Scrape onto a flat surface and form a 9 x 6cm rectangle (doesn’t have to be exact). Wrap in cling film and place in the freezer until very firm. Depending on how powerful your freezer is this can take anywhere between 30 minutes to 2 hours.
Recipe Prep: During this time I recommend getting everything ready for the rest of the recipe. Line up three bowls: one with flour, one with the beaten eggs and the last with the breadcrumbs. Combine the salt, paprika, onion powder and black pepper in a small bowl. Mix half into the flour and the other half into the breadcrumbs. Line a large baking tray with tin foil and place a wire rack on top. Fill a large cast-iron or heavy- based frying pan with the oil.
Slicing: Place the chicken breasts with the thin tail part facing away from you and the thickest end closest to you. Use a small, sharp knife to slice through the middle of the thickest part and very carefully push the knife towards the thin end, making a tunnel through the centre of the chicken. Take your time and be very careful not to slice through the top, bottom or end of the chicken. Any tears or holes will leave room for the butter to leak out. I recommend flipping the chicken a couple of times as you slice through to make sure the knife doesn’t poke outside the chicken.
Once the knife is in you can gently twist it to make the tunnel as wide as you can. The aim of the game here is to make as much for room for the butter as possible. Season both sides of the breast with a pinch of salt and pepper, then repeat with the second breast.
Stuffing: Once the butter has frozen, slice it into three long strips, then slice one of the strips in half. Ideally, you’ll slot one of the short strips into the short side of the breast, and the longer one down the centre. However, this isn’t always achievable, so slice and shape the butter in any way you need to carefully slot as much as you can inside the chicken without it tearing. Make sure you leave a small gap at the opening.
Once the butter is inside, slice off a small piece of stray meat from the edge of the chicken and use it as a plug to cover the opening. This will help prevent the butter from leaking out.
Coating: Coat the chicken in the flour, then the beaten egg, then the breadcrumbs. Dab the thick end with the seam back into the egg and coat in the breadcrumbs again. Repeat this once more to build up a thick crust to prevent the butter from leaking out.
Cooking: Preheat the oven to 180°C/350°F. Heat the oil in the pan over a medium heat until it reaches 180°C/350°F. This will take around 10–12 minutes. When it’s hot enough, a breadcrumb should rapidly sizzle when it hits the oil.
Place the chicken Kyivs in the oil and fry for 2 minutes and 30 seconds. Carefully flip them over and fry the other side for 2 minutes and 30 seconds. Use a spoon to baste any parts of the chicken that aren’t submerged in the oil, namely the end with the seam. Place the chicken on the wire rack set over the foil-lined tray and bake in the oven for 14 minutes.
Serving: Leave to rest for a minute or so before slicing. Spoon over any butter that leaked out, then serve with an extra pinch of salt if desired.