！
A beauty on each arm — nice setup!
Literal
Both-hands [on-に] flowers [with-で] nice environment [casual-じゃん]!
両手に花 is an idiom meaning 'two blessings at once,' typically 'flanked by two beautiful women/people.' Literally 'flowers in both hands.' じゃん is a casual contraction of じゃないか — used for exclamatory assertions meaning 'isn't it!' or 'right!' Very colloquial.