Slice each squach down the middle and wrap each with plastic wrap.
Place wrapped squash, cut side down, in microwave; cook on high until squash is tender, 12 to 15 minutes. Leave squash wrapped while preparing filling.
Heat olive oil in a large skillet over medium heat; cook and stir red bell pepper, radish, leek, celery, jalapeno and pepper, in the hot oil until softened, about 10 minutes.
Add vegetable stock and rice; stir to combine. Cover and simmer until broth is absorbed and rice is tender, about 45 minutes.
Mix greens into rice mixture; cover and simmer for about 7 minutes.
Add curry powder, curry paste, and walnuts to rice mixture; stir to combine.
Unwrap squash and set halves, cut sides up, into 4 soup bowls.
Spoon about 2 tablespoons feta cheese into each squash half.
Add a large scoop of rice mixture atop feta layer.
Top rice mixture layer with any leftover feta.