I will share my personal discovery with you.
Just walk up to the woman of your dreams and politely say these exact words, "Excuse me, may I offer you a compliment?" She WILL say, "Okay." (actually she sometimes will say "What?" like she can't believe her ears) Then simply pick the one thing (beside her weight) that attracted you in the first place, such as: "You have the most beautiful smile." BE SINCERE. Look her in the eyes. The worst she will do is say, "Thank you," and turn away. More often, after "Thanks," she will blush and and the door is open! You follow up with something like, "As a matter of fact, I think you look gorgeous!" She will be receptive for more. Introduce yourself, the rest is up to you. This has worked many times, probably because I acted as a gentleman and showed her respect.