Preheat your oven to 400°F (200°C). Choose a medium baking dish that’s wide enough to spread the tomatoes and artichokes in a single layer.
Add the cherry tomatoes and drained artichokes to the baking dish. Drizzle with the olive oil, add the minced garlic, oregano, and red pepper flakes if using.
Season with a few grinds of black pepper and toss to coat.
Place the block of feta in the center of the dish, nestling it among the vegetables. Drizzle a little extra olive oil over the top of the feta.
Bake for 30–35 minutes, until the tomatoes burst, the artichokes lightly brown at the edges, and the feta is soft and golden on top.
While the feta bakes, bring a large pot of salted water to a boil. Cook the pasta according to package directions until just al dente.
Reserve 1/2 cup of pasta water, then drain.
Remove the baking dish from the oven. Add the fresh spinach directly to the hot dish. Use a spoon to mash the feta and stir everything together until the spinach wilts and a creamy sauce forms.
Add the drained pasta to the baking dish.
Toss gently to coat. Splash in some reserved pasta water as needed to loosen and emulsify the sauce. You want it glossy and silky, not soupy.
Finish with lemon zest and a squeeze of lemon juice for brightness.
Taste and adjust with more pepper, red pepper flakes, or a drizzle of olive oil. If you like, add chopped basil or parsley and a sprinkle of Parmesan.
Serve warm. For a little crunch, top with toasted breadcrumbs or pine nuts.