12 large whole sardines, guts, head, and backbone removed with fillets attached at back
2 allspice berries
10 black peppercorns
5 grams coriander
5 grams chili flakes
500 milliliters red wine vinegar
750 milliliters water
20 grams sugar
20 grams salt
1 large red onion, halved and cut lengthwise in 1-centimeter slices
500 grams shelled English peas
7 grams lemon zest
7 grams mint leaves
175 grams olive oil
Chili flakes (optional)
To Assemble and Serve:
6 large thick slices country bread
For the Sardines:
Season flesh side of the sardines with salt and refrigerate until ready to use.
For the Pickled Onions:
Make a cheesecloth sachet with the allspice, peppercorns, coriander, and chili flakes. Combine the vinegar and water in a small pot and add the spice sachet, sugar, and salt. Bring to a boil and reduce to a simmer for 5 minutes to infuse spices into liquid.
Bring the pickling liquid back to a boil, add the onions, and allow the liquid to quickly come back to a boil. Immediately remove the onions from the liquid and put in a single layer on a cold plate; transfer to a freezer for 3 to 4 minutes. Repeat the process twice more and allow the onions and liquid to cool immediately before putting the onions back in the liquid (with the sachet) in a container with a tight-fitting lid. These will keep for about 2 weeks.
For the Minted Peas:
Bring a medium pot of generously salted water to a boil and set up an ice water bath on the side. Blanch the peas for 1 minute, or until tender but still retaining some texture. Immediately transfer to the ice bath and quickly remove.
Combine the lemon zest, mint, olive oil, and half of the peas in a food processor. Process to a smooth paste and season. Remove from the bowl. Pulse the remaining peas several times in the food processor to just barely chop. Add to the rest of the mixture, stir well, and season. If desired, add chili flakes.
To Assemble and Serve:
Lightly oil the sardines and put them skin-side up on the same sheet pan. Broil for 2 minutes, or until the flesh is just cooked and skin begins to char. Remove from the broiler. Spread the minted peas on each of the bruschetta and top each with two sardines, skin-side up. Garnish with pickled onions and drizzle with olive oil. Serve immediately.
Preheat the broiler to 500ºF. Drizzle the slices of bread with olive oil and put on a sheet pan under the broiler (or on a hot grill) for 2 minutes, or until lightly charred on one side. Flip the slices and repeat. Transfer the bread to a platter.