Is "Our creamiest coffee, now creamier" correct?

Solution 1:

There is an implied notion of time in the statement. Until now or recently this was our creamiest but our changes to it have made it creamier now. As a similar example, our tallest (until recently) daughter is even taller (today).

The key to understanding this grammatically is that in the superlative of yesterday is compared with the superlative of today. Hence, today’s best (superlative) is better (comparative) than yesterday’s best.

British Council : comparatives and superlatives.

Solution 2:

Semantic problem. It could be phrased better with "even creamier". Instead of "now creamier" which sounds funny. Obviously either way it makes sense but phrasing could always be improved.