Set a large lidded skillet over medium heat and let it warm for about 1 minute.

Add the olive oil to the skillet and swirl it to coat the bottom.

Put the sweet potatoes into the skillet and sprinkle them with 1/2 teaspoon of the salt.

Pour the water into the skillet, cover with the lid, and cook for 5 minutes so the sweet potatoes start to soften.

Uncover the skillet and stir the sweet potatoes. Cook for 5 to 6 minutes more, stirring once or twice, until they are almost tender and starting to brown at the edges.

Add the sliced red onion to the skillet with the sweet potatoes.

Cook the onion for 3 minutes, stirring occasionally, until it starts to soften.

Spread the vegetables out in the skillet and add the halloumi pieces in a mostly even layer around them.

Cook the halloumi for 2 minutes, until the undersides look golden. Turn the pieces with tongs or a spoon.

Sprinkle the smoked paprika and the black pepper over the skillet.

Cook for 1 to 2 minutes more, until the second side of the halloumi is lightly browned and the sweet potatoes are tender when pierced with a fork.

Add the baby spinach to the skillet in a few handfuls, stirring gently after each addition so it starts to wilt.