Like its cousins pumpkin and zucchini, Robert squash can be eaten skin-on, especially smaller specimens. To access the flesh, cut off the top cap and remove the seeds inside, just like with pumpkin. For easier removal, blanch by immersing in boiling water for 15-30 minutes, based on size.
Typically boiled in water to soften the flesh, it also excels roasted in the oven or pan-fried—peel first for the pan. Pan-cook after blanching or directly (longer time). Add broth or water when frying to speed cooking.
Patisson squash shines in purées, soups, and beyond. For stuffed squash, cut off the top, hollow out, mix flesh with vegetables or sauce, refill, and bake 30-60 minutes—precook flesh to save time. Stovetop alternative: cube, brown in oiled casserole with carrot sticks and leeks for 30 covered minutes, then add garlic and parsley.