Here is the full list of all 90 Papa's Freezeria Deluxe achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Have 10 different kinds of bubble gum in the lobby at once
Reach Spring
Unlock all Valentine's Day toppings
Master 20 Special Recipes by earning 5 Stars on each
Unlock all New Year toppings
Earn 10 Silver Customer Awards
Unlock all of the Standard Shakers
Unlock all Christmas toppings
Reach Winter
Unlock all of the Standard Whipped Creams
Unlock all Thanksgiving toppings
Earn 5 Prizes or more in each of Foodini's Mini-Games
Earn 15 Special Recipes from customers
Buy any 8 Furniture items from the Shop
Serve all of the Costumed Closers during Halloween
Wear a shirt, belt, jacket, pants, hat, and shoes to match the current holiday
Leave four sundaes on blenders at the end of the day
Unlock all Halloween toppings
Buy any 8 Posters from the Shop
Buy any 4 Flooring or Wallpaper from the Shop
Dress your Chef and Driver in the exact same outfit but with different colors
Buy any 50 items from the Shop
Master 10 Special Recipes by earning 5 Stars on each
Send 10 Customer Coupons to your customers
Get a Perfect Score on 30 orders
Have Kahuna's order ready when he arrives and serve immediately
Use lots of musical furniture so 3 or more customers are dancing in the lobby
Serve Jojo while wearing a Turtleneck and Beret
Get 5 Blue Ribbons from Jojo the Food Critic
Unlock all Maple Mornings toppings
Serve 30 orders to customers in the Dining Room
Have Quinn's order ready when she arrives and serve immediately
Earn 15 Bronze Customer Awards
Reach Autumn
Buy all of the Upgrades in the Shop
Get a 100% Topping Score on 20 orders
Receive your wages on four Pay Days
Serve 100 customers while wearing clothing that matches the season
Buy any 8 Clothing items from the Shop
Unlock all Portallini Feast toppings
Serve 20 delivery orders to customers
Earn 5 Bronze Customer Awards
Grab 250 coins while playing Papa's Raceway
Change your worker's shirt, pants, hat, jacket, and shoes.
Win a Rare Bonus Prize in a Mini-Game by earning a Star Medal
Earn 5 Special Recipes from customers
Master a Special Recipe by earning 5 Special Stars
Unlock all Starlight Jubilee toppings
Earn a Prize in each of Foodini's Mini-Games
Earn 3 Special Stars when serving Today's Special
Don't spend any money in the Shop for 7 days
Get a 100% Build Score on 20 orders
Get a 100% Waiting Score on 20 orders
Get a 100% Mix Score on 20 orders
Serve the first customer last
Reach Summer
Unlock all St. Paddy's Day toppings
Unlock all Easter toppings
Unlock all Big Top Carnival toppings
Unlock all Volcano Gala toppings
Earn 15 Gold Customer Awards
Serve everyone in the Romano Family Quartet
Serve all the band members of Scarlett and the Shakers
Serve all of the customers!
Earn 40 Special Recipes from customers
Unlock all of the Standard Mixables
Unlock all of the Standard Mix Syrups
Unlock all of the Standard Sauce Toppings
Unlock all of the Standard Placeable Toppings
Serve a Chocolate Creameo Special to Captain Cori
Serve a Tropical Treat Special to Tony
Serve a Red Velvet Cake Special to Kingsley
Serve a Vanilla Swizzle Special to Liezel
Serve a Sugarplum Streusel Special to Scooter
Serve a Cinnamon Crunch Special to Marty
Serve a Wildberry Moon Special to Willow
Serve a Caramel Macchiato Special to Akari
Serve a Purple Pom Special to Pally
Serve a Truffle Bomb Special to Treble
Serve a Mighty Mint Special to Mayor Mallow
Serve an Orange Roll Delight Special to Rollie
Use Cotton Candy Syrup in Mandi's sundae
Add Cloudberries to Nevada's sundae
Add Shaved Mints to Edna's sundae
Use Yum n' Ms in Sasha's sundae
Add Pawpaw Topping to Papa Louie's sundae
Serve 20 customers during Christmas wearing a Christmas Hat and Fur Parka
Serve Roy while wearing a Pizzeria Polo and Pizzeria Cap
Serve any 10 sundaes from the Food Truck
Lure 3 regular customers to the Food Truck by preparing their normal order