There are a couple Mexican bakeries in the Pike Place Market and also La Conasupo on Greenwood Ave sells Mexican baked goods. The best pastel de tres leches I've had is from the Salvadorean Bakery in White Center.
I agree, Salvadorean bakery makes an excellent tres leches cake and also has a variety of other pastries and cookies. Guadalupe Market, next to the Goodwill in Burien has a great selection of cookies and pastries, as well as freshly made tortillas.
Salvadorean was exactly what I was looking for. The tres leches was great and so were all the sweets. Had a great lunch to boot. look forward to exploring the neighborhood again. thanks for your suggestions!