With a sharp knife, pierce the squash in 3 or 4 places. Microwave on high power for 2 to 3 minutes, or just until the squash starts to soften under the skin. To test, press with your thumb. Carefully cut the squash into quarters, scoop out and discard the seeds, and cut off and discard the peel. Cut the squash into 1 chunks.
In a large saucepan over medium heat, warm the oil. Add the garlic and cook for 20 seconds or until fragrant. Add the squash, tomatoes (with juice), and water, cover the saucepan, and reduce the heat to medium low. Cook for 25 to 30 minutes, or until the squash is tender but not mushy, adding more water if necessary to keep the squash from sticking. Test for doneness by inserting the tip of a sharp knife in a piece of squash.
With the back of a large spoon, break the tomatoes into smaller pieces. Rinse the kale, strip the leaves from the coarse stems, coarsely chop the leaves, and add to the saucepan. Add the sage and basil. Cook for 3 to 4 minutes, or until the kale softens.