Looking for 50+ year old sci fi book. The Dulgari (sp?) empire has the humans on the run. The hero is a military man who has battled the Dulgari. There are always more of their ships than ours. The initial battle he goes through a series of pre-programmed ship movements, to a draw. Ends up tricking aliens to bring fleet to earth. He signals a "drive mechanism" to start that blows up sun and destroys their fleet and give humans advantage. I remember there being a drink called the "9 Planets".
"The Solarians" by Norman Spinrad (1966).
The novel takes places centuries in the future when humanity has colonized many star systems. Another race, the Duglaari or "Doogs" is slowly conquering human systems
When all seems lost, a stardrive in a ship on Mercury is activated, and Sol explodes, annihilating the Doog fleet.
It also features the drink you mention: 9 Planets. It's a nine layered drink, the punchline being that the ninth layer sobers you up!