Finbourne, the London-headquartered fintech company led by Irishman Tom McHugh, has appointed Banco Santander to advise it on a new series B fundraising round that has already attracted interest from up to 50 potential investors. Finbourne’s revenue is already £20 million but it is expected to double in size over the next 12 months and hit revenue of £100 million in three years. What is it doing that has created so much interest in a company founded just seven years ago?  There was a hint on February 28 when Northern Trust, which has $1.4 trillion in assets under management, announced…