To cook spaghetti squash, the most common and effective method is roasting it in the oven. Here is a detailed guide based on expert sources:

• Preheat your oven to 400°F (204°C).
• Cut the spaghetti squash in half lengthwise. If the squash is too hard to cut, you can soften it by pricking it with a fork and microwaving it in 1-minute bursts or roasting it whole for about 10 minutes before slicing.
• Scoop out the seeds with a spoon.
• Lightly drizzle the inside with olive oil and sprinkle with a little salt and pepper. Avoid too much oil or salt to prevent the squash from becoming watery.
• Place the squash halves cut-side down on a baking sheet.
• Roast in the oven for about 30 to 50 minutes, depending on the size of the squash. Most recommendations suggest roasting for 30 to 40 minutes for a medium squash, but larger ones may take up to 50 minutes. The squash is done when it is fork-tender but still slightly firm and the skin is lightly browned.
• Remove from the oven and let cool enough to handle.
• Use a fork to scrape the flesh into spaghetti-like strands.

This method yields tender but not mushy strands, which is preferred for texture. Cooking times can vary based on the squash size and oven, so check for tenderness with a fork after 30 minutes and adjust as needed

. In summary:

• Roast cut-side down at 400°F
• For 30 to 50 minutes (typically 35-45 minutes)
• Until fork tender but not mushy

This approach is widely recommended for best texture and flavor.