1. Combine a tablespoon of the dune sage with the coarse sea salt. Rub the salt all over the harders, taking care to not get any into the belly cavity. Set the fish aside.
2. Combine the chopped herbs, garlic, lemon zest and juice with a few generous glugs of olive oil. Season the pesto with a pinch of salt and combine to the desired consistency.
3. Shake the excess salt from the harders and braai the fish over hot to medium coals for 3-5 minutes per side, squeezing over fresh lemon juice. The harders are ready once the skin is golden and the flesh pulls away easily from the bones.
4. Serve the harders with the wild greens pesto, lemon wedges, crusty bread and a chilled bottle of Krone Borealis Cuvée Brut.