Home Body Clue chp9

Okay, time for a game of switching.

There are seven cakes; six made by Pinkie Pie, and one made by White. There are seven places at the table. Let's concentrate on identifying who's sitting where first.

Home Body is sitting at the head of the table. (The difficult part here is identifying which end is the head - the end furthest from or closest to the door?)
x x x
      HB
x x x

Next positions given are relative. Scarlet is opposite Plum, and Peacock and Plum are sitting adjacent to each other.

Mustard is sitting with his back to the door, and nearest it, too, near enough to knock White.

Plum settles White into the empty chair between himself and Body. Two possible layouts here:
Pe Pl Wh           xx Sc xx
         HB   or            HB
xx Sc xx           Pe Pl Wh

Body passes the knives left to Green, which finalizes our layout.

Pe Pl Wh
         HB
Ms Sc Gr

Now we know where everyone's sitting; time to head for the dessert. First things first: the cake Body picks out isn't White's. That's fine; he's excluded. For now, anyway.

Let's do an overview of the cakes, then. Three have white frosting, three have blue. Three have fruit in, three do not. It's not clarified how many have extra icing, but let's operate under the assumption that it's also three.

There are more possible permutations than actual cakes, but let's run through them anyway. Two of them must be decoys.
WHITE, no fruit, no icing
WHITE, fruit, no icing
WHITE, no fruit, icing
WHITE, fruit, icing
BLUE, no fruit, no icing
BLUE, fruit, no icing
BLUE, no fruit, icing
BLUE, fruit, icing

Taking White's various recollections throughout the puzzle into consideration, her cake is the (BLUE, no fruit, no icing).

The mares pick blue frosting, the stallions pick white frosting. In addition, nopony on Body's left picked a cake with extra icing.

(BLUE, extra) (WHITE, extra) (BLUE, extra)
(WHITE, no extra) (BLUE, no extra) (WHITE, no extra)

Scarlet swaps her (BLUE, no extra) for one with extra icing. The language used suggests that she trades with White. (At this point, I'm going to guess that absolutely White is going to eat her own cake.)

(Pe, Blue, Extra) (Pl, White, Extra) (Wh, Blue, No extra)
(Ms, White, No extra) (Sc, Blue, Extra) (Gr, White, No extra)

Plum finds fruit. It's implied that Peacock does not, but the pony opposite her (who is Mustard) does, and the latter two swap.
(Pe, Wh, Noex, Fr) (Pl, Wh, Ex, Fr) (Wh, Bl, Noex)
(Ms, Bl, Ex, Nofr) (Sc, Bl, Ex) (Gr, Wh, Noex)

Finally, Green swaps with the only pony who hasn't yet swapped, who is Plum.

(Pe, Wh, Noex, Fr) (Pl, Wh, Noex) (Wh, Bl, Noex)
(Ms, Bl, Ex, Nofr) (Sc, Bl, Ex) (Gr, Wh, Ex, Fr)

Let's grab that list of possible cakes again.
WHITE, no fruit, no icing - PLUM HAS THIS CAKE.
WHITE, fruit, no icing - PEACOCK HAS THIS CAKE.
WHITE, no fruit, icing - By process of elimination, does not exist.
WHITE, fruit, icing - GREEN HAS THIS CAKE.
BLUE, no fruit, no icing - THIS IS THE CAKE WHITE MADE (AND SHE HAS IT).
BLUE, fruit, no icing - By process of elimination, does not exist.
BLUE, no fruit, icing - MUSTARD HAS THIS CAKE.
BLUE, fruit, icing - SCARLET HAS THIS CAKE.

Why? Well, the cakes we know about completely are the ones currently held by Peacock, Mustard and Green - White with fruit but no extra icing, Blue with extra icing but no fruit, and White with fruit and icing. We also know that Blue with no icing and no fruit must exist because White made it.

Plum has a white cake with no extra icing. Since Peacock has the cake with no extra icing but with fruit, Plum must now have one without fruit.

Scarlet has a blue cake with extra icing. Since Mustard has the other blue with icing, and his has fruit, Scarlet's must be the same but without fruit.

By process of elimination, that leaves White to be eating her own cake. Whoops. In the same vein, the white cake with icing but no fruit and the blue cake with fruit but no icing cannot exist, because they go outside the numbers.

Quick numbers double check:
Three blue cakes (WHITE, MUSTARD, SCARLET)
Three white cakes (PLUM, PEACOCK, GREEN)
Three cakes with extra icing (GREEN, MUSTARD, SCARLET)
Three cakes with no extra icing (PLUM, PEACOCK, WHITE)
Three cakes with fruit (PEACOCK, GREEN, SCARLET)
Three cakes without (PLUM, WHITE, MUSTARD)
Everything lines up.

It was WHITE.

Seems like Scarlet dodged a bullet there!