Rognoni d'Agnello allo Sherry

Name: Rognoni d'Agnello allo Sherry
Prep time: 20 min
Cook time: 40 min
Total time: 540 min
Yield: Four plates using two kidneys per guest
Ingredients: 8 Lamb kidneys, whole, skinned, butterflied, and hard white cores scissor-trimmed; 500 ml Milk, optional for refrigerated soaking; use more if needed to cover; 1 tbsp Neutral oil, for searing; 15 g Unsalted butter, for searing; to taste Sea salt and black pepper; 2 Brown onions, medium-large, very thinly sliced; 25 g Unsalted butter; 1 tsp Fresh thyme leaves; small splashes, only as needed Water; one pinch Fine salt; 90 ml Dry sherry; 180 ml Rich lamb or beef stock; 2 tsp Dijon mustard; 0.5 tsp Worcestershire sauce, optional; 25 g Cold unsalted butter, diced; 0.5 tsp Sherry vinegar or lemon juice, adjust to taste; 450 g Potatoes, peeled and coarsely grated; 2 tbsp Clarified butter or neutral oil; 40 g DUKAI Fennel Rosato pickled fennel, drained and finely diced; optional alternative: crisp cucumber pickle; 1 tbsp Chives or flat-leaf parsley, finely chopped; to taste Sea salt

Butterflied Lamb Kidneys, Sherry-Dijon Glaze, Onion Fondue, Crispy Potato and Pickled Fennel

Heart-shaped lamb kidneys, meticulously scissor-trimmed and pan-seared, with dry sherry and Dijon glaze, sweet onion fondue, crisp potato and bright pickled fennel.

Photography in preparation

The complete method is here to read. Original photography will appear when the dish has been documented in the DUKAI kitchen.

A delicate, deeply savoury offal dish that keeps the lamb kidney as the hero. The short sherry-Dijon reduction adds depth, sweet onion fondue contributes softness, and a tiny amount of pickled fennel cuts the richness.

Serves 4 · Four plates using two kidneys per guest · Preparation 20 min · Cooking 40 min · Optional cold milk soak 8 hr

Cook this

DUKAI working kitchen edition. Chef Paul's butterfly-and-scissors technique, dry sherry, Dijon and onion fondue. This formulation is awaiting the next real cooking and photography session; it should not be presented as a completed photographic cookbook plate.
Chef Paul Dukai

Ingredients

Kidneys

Lamb kidneys, whole, skinned, butterflied, and hard white cores scissor-trimmed8
Milk, optional for refrigerated soaking; use more if needed to cover500 ml
Neutral oil, for searing1 tbsp
Unsalted butter, for searing15 g
Sea salt and black pepperto taste

Sweet onion fondue

Brown onions, medium-large, very thinly sliced2
Unsalted butter25 g
Fresh thyme leaves1 tsp
Watersmall splashes, only as needed
Fine saltone pinch

Sherry-Dijon glaze

Dry sherry90 ml
Rich lamb or beef stock180 ml
Dijon mustard2 tsp
Worcestershire sauce, optional½ tsp
Cold unsalted butter, diced25 g
Sherry vinegar or lemon juice, adjust to taste½ tsp

Crispy potato and finish

Potatoes, peeled and coarsely grated450 g
Clarified butter or neutral oil2 tbsp
DUKAI Fennel Rosato pickled fennel, drained and finely diced; optional alternative: crisp cucumber pickle40 g
Chives or flat-leaf parsley, finely chopped1 tbsp
Sea saltto taste

Method

The kidneys

Remove the outer skin, butterfly each kidney lengthwise leaving one hinge, then use small sharp kitchen scissors to snip away the hard white central core and branches. Do not pull.
If desired, cover with cold milk, refrigerate 4 to 8 hours or overnight, discard the milk and dry thoroughly. Keep chilled until cooking.

Onion fondue

Melt 25 g butter in a covered pan, add sliced onions, thyme and salt. Cook gently 25 to 30 minutes, stirring and adding little splashes of water if needed, until meltingly tender and savoury. Keep warm.

Potato rösti

Squeeze grated potatoes very dry in a cloth, season with salt, and form four thin patties.
Shallow-fry in clarified butter over medium heat until golden, 4 to 5 minutes per side depending on thickness. Rest on a rack to stay crisp.

Sherry-Dijon glaze base

Boil 90 ml dry sherry in a small pan until approximately 30 ml remains. Add 180 ml stock and optional Worcestershire; reduce to around 100 ml.
Whisk in the Dijon and keep warm. This base should be ready before the kidneys are seared.

Cook and glaze

Season the dry butterflied kidneys immediately before cooking. Sear in a hot heavy pan with 1 tbsp oil, initially cut-side down, then turn and add 15 g butter.
Reduce the heat and finish gently to 71°C in the thickest lobes, measured with a thin instant-read probe inserted sideways. Timings vary with kidney size and thickness; avoid prolonged simmering.
Transfer to a warm plate. Add prepared sherry-Dijon glaze to the searing pan, scraping up the browned fond. Turn off the heat, emulsify in 25 g cold butter, and finish with sherry vinegar or lemon. Briefly coat kidneys in the sauce.

Plating

Place a spoonful of onion fondue beside or partly under each crisp rösti.
Arrange two heart-shaped kidneys per plate. Spoon just enough glossy sauce around the kidneys to retain their visible shape.
Scatter 1 tsp of drained finely diced pickled fennel onto each plate, then finish with chives or parsley. Serve immediately.

Keeping

Best served freshly cooked. Promptly chill any leftovers; refrigerate at 4°C or below for 3 to 4 days and reheat thoroughly to 74°C.

Allergens and diet

Milk. Mustard. Sulphites. Fish, if anchovy-containing Worcestershire sauce is used.

Last refined · October 2026