When you want a hot drink in cold weather, this kind of thermos is recommended.

Literal

Cold time [at-に] warm drink [subject-が] want [when-時][at-に][topic-は] this-kind-of thermos [subject-が] recommendation.

あったかい is a casual spoken form of 暖かい 'warm.' 魔法瓶 'thermos' — literally 'magic bottle,' a charming Japanese coinage. お薦め 'recommendation' with the polite お prefix. A simple product recommendation.