Causa Limeña

Ingredients

• For the potato layer
• 800 g papa amarilla (Solanum goniocalyx), peeled, boiled whole until tender, riced while still hot
• 60 ml lime juice, freshly squeezed, kept cold
• 40 g ají amarillo paste
• 30 ml olive oil
• 1 tsp fine salt, to season confidently
• For the filling
• 2 ripe avocados, halved, stoned, sliced or mashed at room temperature
• 200 g tuna (canned, drained) or cooked chicken breast, flaked or shredded, at room temperature
• 80 g mayonnaise, at room temperature
• 1 tsp lime juice, to dress the filling
• 1 tsp fine salt, to season the filling

Method

1. 1
   Boil the papa amarilla whole in salted water until a skewer meets no resistance at the centre. Drain immediately and peel while still hot. Rice the potato at once — do not allow it to cool in mass, or residual steam will create moisture pockets.
2. 2
   Pass the hot riced potato through a fine drum sieve into a wide bowl. This removes any remaining fibre and produces a perfectly smooth, uniform purée that will layer with a clean edge in the mould.
3. 3
   While the purée is still hot, add the cold lime juice, ají amarillo paste, and olive oil. Mix by hand only — no processor, no whisk — until the mass is homogeneous, smooth, and a uniform orange-yellow throughout. Season with salt until the potato flavour is full and forward. This is where the dish lives or dies: the temperature contrast between hot potato and cold lime juice, worked only by hand, creates the specific silky texture that defines causa limeña; over-working at this stage produces a gluey, starch-broken paste that cannot be recovered.
4. 4
   Combine the tuna or chicken with the mayonnaise and lime juice. Season with salt. The filling must be at room temperature throughout — test with a fingertip against the inside of the wrist; it should feel neither cool nor warm.
5. 5
   Set a ring mould (approximately 8 cm diameter, 5 cm deep) on a lined tray. Press an even layer of potato purée into the base, compacting it gently so no air pockets remain — the surface should be level and show no seams when seen from the side of the mould.
6. 6
   Spoon the filling over the potato base in a single even layer, taking it to the inner edge of the mould without forcing it into the potato beneath. Lay the avocado over the filling. Press a final, equally thick layer of potato purée over the top, smoothing it flush with the rim of the mould.
7. 7
   Refrigerate until thoroughly cold and set — the mould should feel uniformly cold to the touch on all sides with no soft or warm spot at its centre. Unmould directly onto a chilled plate by lifting the ring cleanly upward; the causa should stand without sliding. Serve at once.