This shop is well known for its Warabi mochi because it's so delicious.
This store is famous for its delicious Warabi mochi.
どちらも「この店のわらび餅は美味しくて有名です。」という意味です。
1) This shop is well known for its Warabi mochi because it's so delicious.
2) This store is famous for its delicious Warabi mochi.
「〜で有名」は
is well known for ~
is famous for ~
と言えます。
「わらび餅」は Warabi mochi とそのまま言う方もいますし、何かわからない人に説明する場合は、It's a Japanese dessert made from bracken starch topped with sweet soybean powder. と言うことができます。
ご参考になれば幸いです!