The Buddha contemplates dependent co-arising in forward order just after his awakening.

Paṭhamabodhi sutta - Upon Awakening (First)

Thus have I heard at one time, the Blessed One was dwelling in Uruvelā on the bank of the river Nerañjarā at the root of the Bodhi tree, having just attained full awakening. Then, for seven days, the Blessed One sat in one posture experiencing the bliss of liberation. At the end of those seven days, the Blessed One, emerging from that stillness of mind, during the first watch of the night, thoroughly paid attention to dependent co-arising in forward order:

"This being, that becomes; from the arising of this, that arises. That is: from ignorance as a condition, formations arise; from formations as a condition, consciousness arises; from consciousness as a condition, name-and-form arises; from name-and-form as a condition, the six sense bases arise; from the six sense bases as a condition, contact arises; from contact as a condition, feeling arises; from feeling as a condition, craving arises; from craving as a condition, clinging arises; from clinging as a condition, continued existence comes to be; from continued existence as a condition, birth comes to be; from birth as a condition, aging and death, sorrow, lamentation, pain, displeasure, and despair come to be. Thus is the arising of this whole mass of suffering."

Then, understanding the significance of this, the Blessed One at that time expressed this inspired utterance:

"When the nature of things becomes evident, to the Brahmin meditating with continuous effort; All his doubts are dispelled, when he knows a thing with its cause."