Combine the water, salt and butter in a saucepan. Bring to a boil and, when boiling, add the lemon juice.

Remove from heat, add the couscous and cover. Let stand for 5 minutes.

In the meantime, heat the olive oil, over medium heat, on a large sauté pan. Add the shallot and garlic and cook for a couple of minutes, until tender and fragrant. Then, add the corn and red pepper flakes and cook for another couple of minutes, until soft.

Transfer the corn mixture to a large bowl. Fluff the couscous with a fork and add to the corn. Add the feta, lemon zest and basil and toss to combine.

Serve warm or at room temperature if serving as a side dish or cold as a salad.