Preheat oven to 400 degrees. Trip and halve the Brussels sprouts lengthwise. Toss on a baking sheet with 1/2 tablespoon olive oil and 1 teaspoon za'atar. Season with salt and pepper, then place in the oven for about 20-25 minutes, until golden brown.

Meanwhile, bring 1 1/2 cups water to boil with the stock concetrate in a small pot over medium heat. Very finely chop the pistachios. Zest and halve the lemon. Roughly chop the dill.

Once boiling, add the couscous to the water with a pinch of salt. Cover, remove from heat, and set aside.

In a small bowl, combine pistachios, panko, half the lemon zest, and remaining za'atar. Season with salt and pepper. Using a spoon or a pastry brush, coat the top of the basa fillets evenly with dijon mustard.

Remove the baking sheet from the oven and move the Brussels sprouts aside to make room for the fish. Place the basa fillets on the baking sheet and season with salt and pepper. Top fillets with panko mixture, pressing breading to adhere. Return the baking sheet to the oven for about 10 minutes, until flaky and opaque.

Fluff couscous with a fork and toss in half the chopped dill and half the lemon zest. Serve basa on a bed of couscous with Brussels sprouts to the side. Finish with a squeeze of lemon on top and a pinch of dill. Enjoy! Tip: For an extra rich sauce, melt 2 tablespoons butter in a pan over medium heat. Add a squeeze of lemon, any remaining dill, and season with salt and pepper. You can use this to drizzle over the basa or stir it into the couscous!