Its Once Upon a Thyme, by Zensho. It is an extremely amazing Dramione fanfic ever!!! In my opinion, Once Upon a Thyme is the best Dramione fanfic ever!!! But Heart of Ice by Dreaming One is great, too!!! ^^
"The Unseemly Proposal" by scarlet-sparx, for sure. It turned me on to fanfics as a whole. It is very well written and sticks the personality of both very closely. Also, they fall in love by degrees so it is very immersive and realistic. Here' the link if you're interested - link