At the Canyon
by Catherine Boger and Trip Payne
The answers to the clues in the first column, in order, are:
CHI
DA
SING
TAR
GI
(Final answer)
TO
DO
HO
IS
MI
KO
SEN
BADEN
YO
CAN
BUDDY
TOM
DOCTOR
AUTHOR
Each of these can be doubled (like an echo "at the canyon"). Putting the doubled words into the appropriate clues in the second column gives:
[HO-HO]'s maker: HOS(T)ESS
[TOM TOM] Club's female founder: WEYM(O)UTH
[BUDDY BUDDY]'s director: WIL(D)ER
[AUTHOR AUTHOR]'s subject: WO(D)EHOUSE
[MIMI]'s ailment: TUBERCU(L)OSIS
[TOTO]'s portrayer: T(E)RRY
[BADEN BADEN]'s region: KA(R)LSRUHE
[ISIS]'s spouse: O(S)IRIS
[CAN-CAN]'s country of origin: FRANC(E)
[DOCTOR DOCTOR]'s city setting: PRO(V)IDENCE
[SEN-SEN]]s improvement aim: BR(E)ATH
[CHI CHI]'s real first name: JUA(N)
[DADA]'s founding city: ZUR(I)CH
[YO-YO]'s best-known manufacturer: DUNCA(N)
[SING SING]'s city: OSSININ(G)
[DODO]'s home: (M)AURITIUS
[KOKO]'s teacher: PATT(E)RSON
[GIGI]'s city setting: P(A)RIS
[TARTAR]'s other name: CA(L)CULUS
Taking the indicated letter of each answer, shown here in parentheses, leads to the clue TODDLER'S EVENING MEAL, whose answer is DIN-DIN. Since "Final answer" is in the first column, though, the final solution is the undoubled version: DIN.