The universe is the reflection of The Goddess, we call her Prakrithi. Her true nature is beyond shape and form, She is the ultimate energy (Shakthi). We have been worshipping her in various forms such as Sarswati, Lakshmi, Durga and Tripura Sundhari etc. By doing this way, we are limiting her transcendence in our perception, which is beyond our contemplation. Concentrate on the Goddess in the form of nothingness, the entire universe and yourself are part of the great nothingness. You get dissolved into Her, into the Great Void. This is Laya Yoga.
VijnanaBhairavaTantra says the same thing like this:
You are Universe
All pervading Nothingness
Merge me into You