How to Make It
In a large pot of boiling salted water, cook the pasta until al dente. Drain the pasta reserving 1 cup of the cooking liquid.
Meanwhile, in a very large, deep skillet, heat the olive oil. Add the garlic and cook over moderate heat until golden, about 1 minute. Add the sambal oelek and stir to combine. Add the pasta along with the cooking liquid and toss to combine. Add the spinach in large handfuls and stir until wilted. Season lightly with salt. Add the feta and cook over moderately high heat, stirring until the feta is melted and the pasta is suspended in a thick creamy sauce, about 3 minutes longer. Serve right away.