"more than an ordinary ramen shops extra serving."
"larger than an ordinary ramen shops large serving."
- "more than an ordinary ramen shops extra serving."
"more than ~" 「〜よりも多い」
"an ordinary ramen shops" 「普通のラーメン屋の」"an ordinary" の代わりに "a regular" も使えます。
"extra serving" 「大盛り」"large serving" も使えます。
- "larger than an ordinary ramen shops large serving."
"larger than ~" 「〜よりも大きい」
The amount of noodles you get with a regular size serving here is more than the extra helping you get at other restaurants.
ーThe amount of noodles you get with a regular size serving here is more than the large serving you get at other restaurants.
「ここの並盛りのラーメンの量は他の店の大盛りより多い」
the amount of noodles で「ラーメンの量」
a regular size serving で「並盛り」
A is more than B で「AはBより多い」
large serving で「大盛り」
ちなみに extra helping で「おかわり」
ご参考まで！
オーストラリア 
カナダ 
