Golden Piece of Cake

Upgrade	Effect	Sell value	Magic Powder
+0	+5% base speed · +6% Coins	15,834	160
+1	+5% base speed · +6.2% Coins	16,464	163
+2	+5% base speed · +6.4% Coins	17,262	168
+3	+5% base speed · +6.6% Coins	18,228	174
+4	+5% base speed · +6.8% Coins	19,362	186
+5	+5% base speed · +7% Coins	20,664	199
+6	+5% base speed · +7.2% Coins	22,134	212
+7	+5% base speed · +7.4% Coins	23,655	273
+8	+5% base speed · +7.7% Coins	25,332	340
+9	+5% base speed · +8% Coins	27,165	414

Extracting this Treasure returns Magic Powder. The amount is fixed per Treasure and upgrade level — it does not depend on which ingredients were used to evolve it.

The priciest slice of all—reserved for the main character only!