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