Yes I think it is do-able, but it won't be easy. Without giving it too much thought, there are two ways you can do this. One is a declaration of trust stating that your husband is the sole beneficial owner but if the house is sold or you separate you get an interest. I foresee that presenting a problem to the mortgage company though.
The alternative is for you to transfer the property to your husband absolutely, backed by a separate agreement he will execute a legal charge in your favour for 50%. He then gets the mortgage (as first legal charge), you then take the second legal charge. That way, the mortgage company are not in anyway prejudiced.