Heat oil in a large frying pan over medium heat, add shallot and sauté until tender (3-4 minutes). Add peas and stock, simmer until just tender (2-3 minutes). Stir through lemon rind, season to taste, spoon onto a serving platter and arrange lardo slices on top. Serve warm with trout.
Note Lardo is pork back fat that has been
salted and cured. It's available from select delicatessens and