Cranmer like most figures in church history was prolific and even this single volume Writings and Disputations Relative to the Lord's Supper, focused on solely on Communion is massive and I've only got it on short term loan. So admittedly I'm skimming the surface here, but even then it looks helpful.
I'm trying to get at what is spiritually significant about the Lord's Supper. During Communion we are "participating in Christ's blood" ( Cor 10:16), taking symbols that represent his body and blood, given for our salvation (Matt 26:26-28) and in doing so "proclaiming his death" (1 Cor 11:26). To show how closely we are tied to him, Jesus uses semi-cannibalistic language. (John 6:46-58) It's not that feeding on Jesus will make us united with him; that would put us in the awkward position of either having only to eat once (yah, safe with Jesus forever because I've eaten the holy food), or having to take the Lord's supper every few hours after we've digested him previously. It's because we have this intimate, food-like-bond with Jesus that we can eat, the Lord's Supper presumes Union with Christ. But this still leaves us with the question of what spiritually happens when we have communion?
So what does Cranmer say about whether or not Christ is present in the bread and wine; "And although we do affirm (according to God's word), that Christ is in all persons that truly believe in him, in such sort, that with his flesh and blood he doth spiritually nourish and feed them, and giveth them everlasting life, and doth assure them thereof, as well by the promise of his word, as by the sacramental bread and wine in his holy supper, which he did institute for the same purpose; yet we do not a little vary from the heinous errors of the papists. For they teach, that Christ is in the bread and wine; but we say (according to the truth), that he is in them that worthily eat and drink the bread and wine." ( Writings and Disputations, 52)
Can Cranmer shed any light on what eating and drinking during Communion actually does? "And every good and faithful christian man feeleth in himself how he feedeth of Christ, eating his flesh and drinking of his blood. For he putteth the whole hope and trust of his redemption and salvation in that only sacrifice, which Christ made upon the cross, having his body there broken, and his blood there shed for the remission of his sins. And this great benefit of Christ the faithful man earnestly considereth in his mind, chaweth and digesteth it with the stomach of his heart, spiritually receiving Christ wholly into him, and giving again himself wholly unto Christ." ( Writings and Disputations, 208)