The most appropriate verb to fill in the blank is has. 

This is a subject-verb agreement question involving the correlative conjunction "Either... or..."

The rule is: When two subjects are joined by "either... or...", the verb agrees with the subject nearest to it.

1. Sentence: Either Savita or her daughter _____ made this delicious pudding.

2. Subjects: "Savita" (singular) and "her daughter" (singular).

3. Nearest Subject to the verb: "her daughter" (singular).

4. Tense: The main verb "made" suggests a perfect tense structure (Auxiliary verb + Past Participle).

5. Required Verb: The singular auxiliary verb for the perfect tense is has.

Therefore, the correct sentence is: "Either Savita or her daughter has made this delicious pudding."