Biscuit that’s Greek eclipsing Scandinavian one? They’re the same! (10)

'biscuit' is the definition.
(I know that gingersnap is a type of biscuit)

'greek eclipsing scandinavian one? they're the same' is the wordplay.
'greek' becomes 'gr' (abbreviation for Greek).
'eclipsing' means one lot of letters goes inside another (eclipse can mean to cover up or hide).
'scandinavian one?' becomes 'Inge' (Inge is a common Scandinavian name).
'they're the same' becomes 'snap' (as in the card game).
'gr' enclosing 'inge' is 'ginger'.
'ginger'+'snap'='GINGERSNAP'

'that's' acts as a link.