Head out to Lake Poway and take the Mt.Woodson peak trail. You won't miss it, as it's right along the path very near the top.
It gets cold in the winter. Bring warm clothes. Also, if you're taking the hike later in the afternoon, park outside of the park area because they lock down at sunset.
The peak of Mt. Woodson is home to a unique rock formation. A massive shearing left nothing but a potato chip of rock. It overhangs a significant drop, but makes uphill hike well worth it.